HistoricSiteMarkers

Historic Markers in Pennsylvania

2,561 markers in the database — showing 1,0811,140.

Helen Furnace

Highland Township, PA

In the wooded hills of Clarion County, the stone stack of the Helen Furnace still stands as a relic of Pennsylvania's antebellum iron boom. Built in 1845, this was a cold-blast charcoal furnace—an early industrial technology that smelted local iron ore using heat drawn from surrounding hardwood forests. It was one of dozens of such furnaces that dotted the county between roughly 1829 and 1867, when the region earned the nickname "The Iron County" for the sheer density of its ironworks.

Helen Richey (1909-1947)

McKeesport, PA · est. 2002

Helen Richey of McKeesport broke into the sky in 1934 when she became the first woman to fly a commercial airliner — only to face such hostility from male colleagues that she resigned within a year. Undeterred, she became the first woman licensed as an instructor by the Civil Aeronautics Authority. When war came she rose to command the American wing of Britain's Air Transport Auxiliary, flew with the Women's Airforce Service Pilots, and finished the war a Major.

Henry A. Muhlenberg

Reading, PA · est. 1951

The home of Henry A. Muhlenberg stood on this site in Reading, heart of Pennsylvania's German Lutheran community. Muhlenberg served nearly three decades as pastor of Trinity Lutheran Church before entering public life as a congressman, the first U.S. Minister to Austria, and a candidate for governor at his death in 1844. He carried the influence of the region's Pennsylvania German churches into national and diplomatic affairs.

Henry Chapman Mercer (1856-1930)

Doylestown Township, PA · est. 1998

At the turn of the twentieth century, Henry Chapman Mercer helped lead the American Arts and Crafts movement from the quiet county seat of Doylestown. A trained archaeologist who feared industrialization was erasing the tools of everyday life, he both revived handmade ceramic tile and amassed a sprawling collection of preindustrial American implements. Between 1908 and 1916 he poured three fantastical reinforced-concrete buildings — his home Fonthill, his tile works, and his museum — that still stand as some of the boldest early experiments in that material.

Henry Clay Frick

East Huntingdon Township, PA · est. 1946

Here in the Pennsylvania countryside near West Overton, one of America's most formidable industrialists began life in a modest homestead tied to the Overholt distilling family. Henry Clay Frick rose from these rural roots to build a coke and steel empire, partnering with Andrew Carnegie and turning the region's coal into the fuel that fired the nation's furnaces. The preserved Overholt home now interprets both the whiskey-making family that raised him and the Gilded Age fortune he went on to amass.

Henry Clay Frick (1848-1919)

Pittsburgh, PA · est. 1946

Henry Clay Frick rose to become one of the titans of Gilded Age Pittsburgh, building a fortune in coke — the refined coal that fed the blast furnaces of the steel age — before helping lead Andrew Carnegie's steel empire. As chairman of Carnegie Steel, his hard line against organized labor helped ignite the violent 1892 Homestead Strike, in which workers and Pinkerton agents fought a deadly pitched battle. Frick later turned his wealth toward philanthropy and art collecting.

Henry George

Philadelphia, PA · est. 1984

The economist Henry George was born on this Philadelphia spot on September 2, 1839, and went on to write "Progress and Poverty," a book that sold in the millions and made him one of the most widely read thinkers of the Gilded Age. He argued that society should tax the value of land — a value the community creates — rather than the fruits of individual labor and capital. His "single tax" ideas sparked reform movements at home and abroad before his death in New York in 1897.

Henry J. Heinz (1844-1919)

Pittsburgh, PA · est. 1994

Henry J. Heinz began in 1869 with a humble product — bottled horseradish sold from a Pittsburgh garden — and built it into one of the world's great food empires within two decades. In an era of adulterated and mislabeled food, Heinz staked his brand on purity, selling his condiments in clear glass so buyers could see exactly what they were getting. He paired shrewd, theatrical advertising with unusually generous treatment of his workers, reshaping both how Americans ate and how businesses sold to them.

Henry L. Phillips (1847-1935)

Philadelphia, PA · est. 1993

Henry L. Phillips traveled a remarkable spiritual path—baptized Catholic, raised Moravian, and ultimately ordained an Episcopal priest—before turning the Church of the Crucifixion into far more than a house of worship. Under his leadership it became a Black cultural center renowned for its social outreach in Philadelphia. He also helped found the American Negro Historical Society, an early effort to document and preserve African American history.

Henry M. Hoyt

Kingston, PA · est. 1952

Henry M. Hoyt was born on this site in 1830 and rose to become governor of Pennsylvania from 1879 to 1883 — the first to serve a full four-year term under the reforming state Constitution of 1873. His administration fell in the industrial ferment of the Gilded Age, and he pressed for correctional institutions aimed at the care and reform of young offenders. He died in 1892.

Henry Noll

Bethlehem, PA · est. 1995

Henry Noll was a Bethlehem Steel laborer whose extraordinary output—said to be 45 tons of pig iron loaded in a single day in 1899—became the human centerpiece of Frederick W. Taylor's influential book, Principles of Scientific Management. Disguised as "Schmidt" in Taylor's writings, Noll's willingness to work for a raised daily wage of $1.85 helped Taylor argue that careful measurement could multiply productivity. The story shaped how factories, offices, and armies would organize work for a century.

Henry Norwood "Barney" Ewell (1918-1996)

Lancaster, PA · est. 2018

Barney Ewell of Lancaster was one of the fastest men alive in the years when there were no Olympics to prove it—the 1940 and 1944 Games were cancelled by World War II, robbing him of his athletic prime. A star at McCaskey High School and Penn State, he refused to quit, and in 1948 at age thirty he tied the world record in the 100 meters at the U.S. Olympic Trials. At the London Games that summer he came home with a gold and two silver medals.

Henry O. Tanner (1859-1937)

Philadelphia, PA · est. 1991

Henry Ossawa Tanner lived here while training at the Pennsylvania Academy of the Fine Arts, one of the few Black students at the prestigious school. His early canvases portrayed the dignity and quiet humanity of ordinary African-American life. Seeking wider acceptance, he moved to Paris, where he turned to religious subjects and earned international acclaim as one of the most celebrated American painters of his generation.

Henry R. Rouse

Rouseville, PA · est. 1996

Henry R. Rouse traded the schoolroom and the Warren County legislature for the booming oil fields of northwestern Pennsylvania, where new leaseholders were making fortunes almost overnight. On April 17, 1861, he was among nineteen people killed when the Little & Merrick well exploded and burned; mortally injured, he dictated a will that left generously for local roads and the poor. The village had just been renamed Rouseville in his honor, and among its residents was a young Ida Tarbell, who would grow up to become the oil industry's most famous critic.

Henry's Gun Factory

Plainfield Township, PA · est. 1974

About 1800, William Henry II built a firearms works in this Northampton County valley, part of a noted gunmaking family whose craftsmanship armed Americans across generations. Rifles and muskets made here supplied troops in the War of 1812, and the Henry name endured on shotguns produced as late as 1904. The factory was one of the small, skilled arms shops that gave the young nation its firepower.

Henrys Tannery

Jackson Township, PA

In the wooded ridges of Perry County stood Pandemonium, one of the small industrial hamlets that sprang up across 19th-century Pennsylvania wherever water, bark, and hides could be brought together. Henry's tannery turned oak and hemlock bark into the tannin that cured leather, an essential trade before synthetic chemistry. When the bark ran out and demand shifted, the town emptied, leaving only foundations and the tannery ruins behind.

Henszey's Wrought Iron Arch Bridge

East Pennsboro Township, PA · est. 2004

Patented in 1869 by Joseph G. Henszey and built the same year by Philadelphia's Continental Bridge Co., this wrought iron bowstring arch truss is an early survivor of the bridge-building boom that followed the Civil War. It first carried traffic over Trout Creek in Slatington, was relocated in 1900 to span Ontelaunee Creek, and in 2002 moved again to Summerdale to carry pedestrians. Few of its kind remain.

Hereford Furnace

Hereford Township, PA · est. 1967

Thomas Maybury established this furnace on the Perkiomen Creek in 1745 to smelt the iron that colonial Pennsylvania increasingly demanded. Tradition credits the works with producing, in 1767, the first cast-iron cooking stove made in North America—an everyday innovation that would warm and feed countless homes. The site reflects the ingenuity of the colony's early ironmasters.

Heritage Park Workers Memorial

Reading, PA

Reading grew into one of Pennsylvania's great manufacturing cities, its fortunes built on railroading, iron and steel, textiles, and hardware that drew generations of laborers to its mills and shops. This memorial, dedicated in 1991 within a park set aside to honor that heritage, pays tribute to the working men and women whose daily toil powered the city's rise. Rather than marking a single event, it stands for an entire industrial community and the ordinary people who kept its furnaces lit and its trains running.

Herman Herzog (1831-1932)

Philadelphia, PA · est. 2011

In the decades after the Civil War, Philadelphia was a magnet for artists drawn to the nation's Centennial celebrations and its thriving cultural institutions. Herman Herzog, already celebrated in his native Germany with patrons among Europe's royalty, settled in the United States in the 1860s and turned his brush to America's sweeping, unspoiled scenery in the spirit of the Hudson River School. From his home and studio here he produced an extraordinary body of landscape work and raised a son, Lewis, who followed him into art.

Hershey

Derry Township, PA · est. 2003

In 1903, candy maker Milton S. Hershey set out to build not just a factory but an entire community around it. The model town of Hershey rose from Pennsylvania farmland, complete with housing, schools, parks, utilities, a transit system, and cultural institutions — all orbiting the world's largest chocolate factory, which opened in 1905. It became both an industrial powerhouse and a celebrated tourist destination.

Hershey's First Candy Store

Philadelphia, PA · est. 2009

In the summer of 1876, as Philadelphia hosted the Centennial Exhibition and the nation marked its hundredth birthday, an eighteen-year-old Milton S. Hershey opened a modest confectionery here, selling candies, nuts, and baked goods. The venture found early customers but foundered on the shoals of credit and debt. That failure was only a beginning: Hershey went on to build the Lancaster Caramel Company and then the chocolate empire that made his name a household word.

Hessian Camp

Reading, PA · est. 1949

When General Burgoyne's British army surrendered at Saratoga in 1777, thousands of captured German auxiliary troops — most of them Hessians hired by the Crown — became prisoners of war held far from the fighting. Some were marched to Reading, where from 1781 to 1783 they lived in a camp of huts on the hillside just north of this spot. Many of these soldiers, once enemies, would remain in Pennsylvania after the war and settle among its German-speaking communities.

Hickory Grove Cemetery

Waverly Township, PA · est. 2003

Established in 1807 in what was then called Abington Center, Hickory Grove Cemetery is among the oldest known burial grounds tied to African Americans in northeastern Pennsylvania. Many of those laid to rest here were fugitives from slavery who reached Waverly by the Underground Railroad, part of a community that numbered some 75 former slaves by century's end. The cemetery remains the enduring trace of that vanished community.

Hickory Town

Hickory Township, PA · est. 1947

Across the river from this point stood the "Middle Town" of the Goschgoschink cluster, later called Hickory Town, one of the Native refuge villages the Moravian missionary David Zeisberger came to in 1767. Here Zeisberger held his celebrated debate with Wangomen, a Munsee religious leader who challenged the missionary's Christian teaching — a rare recorded clash of spiritual worldviews on the colonial frontier. The town also marked the northern end of Indian paths running up from the south, along which trade goods reached these upper-Allegheny communities.

Hiester Home

Reading, PA · est. 1951

From about 1792 until his death in 1832, this Reading site was the home of Joseph Hiester, whose life spanned the founding era. He fought as a lieutenant colonel in the Continental Army, sat as a delegate to Pennsylvania's Provincial Convention in 1776, served fourteen years in Congress, and capped his career as governor of Pennsylvania from 1820 to 1823.

Hilary Koprowski, M.D. (1916 - 2013)

Philadelphia, PA · est. 2024

Polish-born Hilary Koprowski fled the turmoil of mid-century Europe and became one of America's most consequential medical scientists. Before arriving in Philadelphia he had developed the first successful live oral polio vaccine, and as director of the Wistar Institute from 1957 to 1991 he built it into a world-leading biomedical research center. Under his leadership the institute produced vaccines for rubella, rabies, and rotavirus and pioneered the use of monoclonal antibodies in fighting cancer.

Hilda Doolittle (H.D.)

Bethlehem, PA · est. 1982

The poet Hilda Doolittle — known to the literary world simply as H.D. — was born in Bethlehem in 1886 and grew into one of the pioneering voices of the Imagist movement. Reaching back to ancient Greece for her spare, luminous style, she pursued what her marker calls the Hellenic spirit and a classic beauty of expression across a career that spanned continents. She died in Zurich in 1961 and rests in nearby Nisky Hill Cemetery.

Hill's Tavern

North Bethlehem Township, PA · est. 1952

Stephen Hill opened this tavern in 1794, and it has poured for travelers ever since, making it one of the oldest houses of entertainment on what became the National Road. Stagecoaches changed teams here and heavy Conestoga wagoners bunked down for the night as freight and passengers rolled between the eastern seaboard and the Ohio country. Taverns like Hill's were the roadside infrastructure of early overland travel.

Hilldale Athletic Club (The Darby Daisies) (The)

Yeadon, PA · est. 2006

From 1910 to 1932, the Hilldale Athletic Club played its home games here at Hilldale Park, becoming one of the powerhouse franchises of Black baseball. Known as the Darby Daisies, the club won three Eastern Colored League pennants and captured the 1925 Negro League World Series. Its rosters read like a Hall of Fame ballot, featuring Pop Lloyd, Judy Johnson, Oscar Charleston, and Biz Mackey, while owner Ed Bolden helped organize the Eastern Colored League itself.

Historic Fallsington

Falls Township, PA · est. 1961

Fallsington grew up as one of the earliest settlements in William Penn's new colony, a Quaker village in Bucks County whose Friends Meeting was organized in 1683. Penn himself worshiped here in 1701, and over the centuries the village kept a remarkable collection of its provincial-era houses. The original 1692 meetinghouse once stood near the site of the present one, anchoring a community shaped by Quaker faith and Penn's ideals.

Historical Society of Pennsylvania

Philadelphia, PA · est. 2010

Founded in 1824 by prominent Philadelphians, the Historical Society of Pennsylvania is among the oldest institutions of its kind in the nation and has occupied this site since 1884. Its special collections hold many of the country's foundational documents, chronicling American life from the seventeenth century onward. The Society emerged in the Early Republic's surge of civic and antiquarian energy, as a young nation set out to preserve its own record.

Hockendauqua - PLAQUE

Allen Township, PA · est. 1925

In the tangled early history of Penn's Woods, this ground sat beside an Lenape (Delaware) town near the Lehigh River, home to leaders the colonists knew as Lappawinzo and Tishcohan. Their names are bound to the notorious Walking Purchase of 1737, when Pennsylvania's proprietors used a decades-old, dubiously drawn deed to claim land measured by a day-and-a-half's walk. The colony hired fast, trained walkers like Edward Marshall, who strode far beyond what any ordinary traveler could cover, extending the boundary and stripping the Lenape of vast holdings.

Holbert Racing 1953-1988

Warrington Township, PA · est. 2021

For decades a Bucks County family turned a passion for speed into one of the great names in American motorsport. Bob Holbert ran one of the country's first Porsche dealerships and racked up national championships behind the wheel of Porsches and Shelby Cobras beginning in 1953. His son Al became a dominant endurance driver, winning IMSA GT titles, a record haul of race victories, and three overall wins at the grueling 24 Hours of Le Mans.

Holley Motor Company

Bradford, PA · est. 2008

In 1899, brothers George and Earl Holley began building engines and cars in Bradford, and the carburetor on their Motorette caught the eye of Henry Ford. Specializing in that technology, the Holley Motor Company became a leading supplier to Ford and, in time, to the aircraft industry and the U.S. military. The name endures today as a byword for high-performance carburetors.

Holy Trinity Lutheran Church

Lancaster, PA · est. 1975

Founded in 1730, this Lancaster congregation stood at the heart of a bustling colonial town where the Pennsylvania frontier met the settled east. Its early building even hosted a 1762 Indian treaty council, a reminder that diplomacy with Native nations often unfolded in the plainest of civic spaces. The stone church dedicated in 1766 still guards the graves of two Pennsylvania statesmen of the Revolutionary era, Thomas Wharton and Governor Thomas Mifflin.

Holy Trinity Roman Catholic Church

Philadelphia, PA · est. 2023

Founded in 1787 by German-speaking Catholics who wanted to worship and pass on their traditions in their own language, Holy Trinity became the first German national parish in the United States. Its church rose in 1788–1789, and within a few years its congregation and cemetery included African Americans and refugees from the upheaval in Saint-Domingue, buried alongside parishioners of European descent. The model of the ethnic 'national parish' it pioneered would shape American Catholicism for generations before the parish finally closed in 2009.

Homestead Grays

Homestead, PA · est. 2000

Founded by Homestead steelworkers around 1900, the Homestead Grays grew into one of the most dominant franchises in all of baseball history. Under the leadership of Cumberland Posey Jr., the Grays captured twelve national titles — including nine in a row from 1937 to 1945 — and fielded Hall of Famers like Josh Gibson, Buck Leonard, and Smokey Joe Williams. Playing in the segregated Negro Leagues, they were a source of fierce pride for African Americans in Pittsburgh and far beyond before disbanding in 1950.

Homestead Strike

Munhall, PA · est. 1992

At dawn on July 6, 1892, the Homestead Strike erupted into open battle when 300 Pinkerton agents, hired on behalf of Carnegie Steel, tried to land by barge to break the union's hold on the mill. Strikers and townspeople drove them back in a bloody firefight that left seven workers and three Pinkertons dead. Days later 8,000 state militia marched in to restore the company's control, and by November the strike—and the union—had been crushed.

Homestead Strike Victims

Munhall, PA · est. 1993

In the summer of 1892, workers at Andrew Carnegie's Homestead steelworks clashed with a barge-load of Pinkerton guards hired to break their union during a bitter lockout. The July 6 gun battle along the Monongahela left men dead on both sides and became one of the defining confrontations of American labor history. Buried in these two adjoining cemeteries are six of the seven steelworkers who died, ordinary men whose graves mark the human cost of the struggle between organized labor and industrial capital.

Honesdale

Honesdale, PA · est. 1948

Laid out in 1827 at the head of the Delaware & Hudson Canal, Honesdale took its name from Philip Hone, the New York merchant and celebrated diarist who championed the canal and the region's anthracite coal trade. The town became the point where hard coal met the waterway that carried it toward eastern markets, and it grew important enough to become the Wayne County seat by 1841. Its founding tied a remote Pennsylvania valley into the great commercial machinery of the young republic.

Honey Hollow Watershed

Solebury Township, PA · est. 1997

In 1939, six farms along a Bucks County creek joined together in an experiment that would reshape how Americans cared for their land. Working with federal soil experts, they showed that neighbors cooperating across property lines could halt erosion and protect water and wildlife better than anyone acting alone. The idea proved so successful that it became a model copied by thousands of watersheds nationwide, and the site was named a National Historic Landmark in 1969.

Honus Wagner (1874-1955)

Carnegie, PA · est. 1998

Honus Wagner, the "Flying Dutchman," was born in 1874 to German immigrants and lived his whole life in Carnegie. Widely hailed as baseball's greatest shortstop and one of its finest all-around players, he starred for the Pittsburgh Pirates from 1900 to 1917, winning a record eight National League batting titles and later coaching the team. Admired for his modesty and sportsmanship, he became one of the five charter members inducted into the Baseball Hall of Fame in 1936.

Hope Lodge

Whitemarsh Township, PA · est. 1966

Hope Lodge is a graceful stone mansion built around the middle of the 18th century, prized today as a fine example of Georgian architecture with its balanced proportions and formal symmetry. Standing in Whitemarsh Township, it reflects the wealth and refined taste of colonial Pennsylvania's gentry. It is now preserved and administered by the Pennsylvania Historical and Museum Commission.

Hopewell Forge Mansion

Elizabeth Township, PA · est. 1959

Around 1740, ironmaster Peter Grubb built this house amid the forges and furnaces that made Pennsylvania a colonial iron powerhouse. Grubb had opened the nearby Cornwall Furnace, tapping the region's rich ore, while the Upper and Lower Hopewell Forges hammered pig iron into usable bar iron along Hammer Creek. The dams that once powered those forges can still be traced in the water below the mansion.

Hopewell Historic District

East Nottingham Township, PA · est. 1996

Chartered as a borough from 1853 to 1914, Hopewell was a small Chester County valley remade into a showcase of forward-looking farming, milling, and schooling. Drawn by its water power, the Dickey family developed the valley between 1815 and the 1870s, with Samuel Dickey earning a reputation as an agricultural innovator and his kin founding local schools. Much of that 19th-century landscape of fields and buildings still survives today.

Hopewell Village

Exeter Township, PA · est. 1947

A few miles south of here stood Hopewell, one of the great charcoal-iron plantations of southeastern Pennsylvania—its forge dating to 1744 and its furnace to 1770. Around the furnace grew a self-contained community of ironmasters, molders, colliers, and their families whose lives ran to the rhythm of the blast. The furnace and its village survive today under the National Park Service as a window into early American industry.

Hopewell Village

Exeter Township, PA · est. 1947

A few miles south of here stood Hopewell, one of the great charcoal-iron plantations of southeastern Pennsylvania—its forge dating to 1744 and its furnace to 1770. Around the furnace grew a self-contained community of ironmasters, molders, colliers, and their families whose lives ran to the rhythm of the blast. The furnace and its village survive today under the National Park Service as a window into early American industry.

Horace Pippin

West Chester, PA · est. 1979

Horace Pippin returned from World War I with a wounded right arm and, undeterred, taught himself to paint by guiding his brush with his other hand. From this West Chester house he produced some of the most powerful American folk paintings of the 20th century, including his searing meditations on abolitionist John Brown and his radiant "Holy Mountain" series. Discovered by the art world in the late 1930s, he became one of the most celebrated self-taught Black artists of his era.

Horse-Shoe Trail Eastern Terminus

Upper Merion Township, PA

The Horse-Shoe Trail was blazed in 1935 as a bridle-and-hiking path linking the hallowed ground of Valley Forge — where Washington's Continental Army endured the brutal winter of 1777–78 — to the Appalachian Trail on Stony Mountain, winding 121 miles through the rolling farmland and wooded ridges of southeastern Pennsylvania. This granite marker, set in 1972 by the Horse-Shoe Trail Club, honors Henry M. Woolman, one of the volunteers whose vision knit together a footpath still walked today. Trails like this one grew out of the early-twentieth-century outdoor movement, when clubs of enthusiasts carved recreational corridors across the American landscape.

Hosanna Meeting House

Upper Oxford Township, PA · est. 1992

Built by free Black families in the Chester County countryside, this meeting house grew from an informal "African Meeting House" into a formally organized African Union Methodist Protestant congregation in 1843. It doubled as a station on the Underground Railroad, sheltering freedom-seekers on their way north. Among those who spoke or passed through were Frederick Douglass and Sojourner Truth.

Hotel Brotherhood USA

Philadelphia, PA · est. 2016

Founded in 1883, the Hotel Brotherhood USA was a benevolent society of Black hotel workers that grew into one of the most influential early organizations in the hospitality trade. In an era when Black laborers had few protections, it championed fair treatment, dignity on the job, and economic self-reliance, pooling resources to support its members. It has been headquartered at this Philadelphia location since 1906.

Hotel Fauchere

Milford, PA · est. 2007

Opened in 1852 as a summer retreat in the Pocono foothills, the Hotel Fauchere earned national fame for its kitchen once Louis Fauchere—a master chef trained at New York's celebrated Delmonico's—took charge. He brought fine ingredients, refined recipes, and the then-novel idea of the printed menu to a small Pennsylvania town. Over the decades its guest register filled with presidents, governors, artists, and writers drawn to its elegant table.

House of Industry

Philadelphia, PA · est. 1996

Opened in 1846, this was the first institution of its kind in Pennsylvania, meeting the surging need of a city swelling with newcomers. It served Irish Catholic and other immigrants alongside the native-born, offering relief to the poor in an era before any government safety net. Rather than mere charity, it emphasized training programs meant to help the needy find work and stand on their own.

Howard Zahniser

Tionesta Township, PA · est. 2001

Howard Zahniser, who made Tionesta his hometown, was the principal architect of the Wilderness Act of 1964. As executive director of The Wilderness Society and editor of its journal, he drafted and championed the legislation through years of political struggle, writing the law's memorable definition of wilderness as a place 'where man himself is a visitor who does not remain.' He died just months before President Lyndon Johnson signed the bill into law.

Huber Coal Breaker

Ashley, PA · est. 2017

Rising over the anthracite fields of Luzerne County, the Huber Coal Breaker was built by the Glen Alden Coal Company in 1939 to crush, sort, and clean up to 7,000 tons of hard coal a day. It was among the first to use Menzies cones to separate coal from rock and an aerial tramway to haul off waste, and its product was famously dyed to market Glen Alden's trademarked "Blue Coal." When anthracite demand faded, the breaker shut down in 1976 and was demolished in 2014, closing a chapter in the region that once heated much of the nation.

Humboldt Refinery

Cornplanter Township, PA · est. 2001

Along Cherry Run in Venango County, chemist Jon Bruns and the Lodovici Brothers opened the Humboldt Refinery in 1862, in the heart of the region where America's oil industry was born only a few years earlier. Named for the great naturalist Alexander von Humboldt, the 47-acre works was among the largest and most scientifically advanced refineries of its day, featuring a two-mile pipeline, oil-fired boilers, and even aniline dye production. It ran until 1868, a brief but ambitious chapter in the frenzied early oil boom.

Hummelstown Brownstone Quarries

Hummelstown, PA · est. 2005

From 1863 to 1929, quarries near Hummelstown cut a rich, even-grained brownstone prized by builders across the country as a fashionable masonry stone. The Hummelstown Brownstone Company, founded by Allen Walton, drew immigrant stone-cutters and laborers whose skilled hands shaped the blocks that faced churches, rowhouses, and public buildings far beyond Pennsylvania.

Humphry Marshall (1722-1801)

West Bradford Township, PA · est. 2014

Humphry Marshall, a Chester County Quaker, became one of the first commercial nurserymen in the new nation and, in 1785, wrote Arbustum Americanum: The American Grove, the first book on North American trees and shrubs by an American. From the house he built here, he shipped native plants to eager European collectors curious about the flora of the New World. His work earned him the title Father of American Dendrology, and his specimens graced the royal gardens of King George III and King Louis XVI.

Hunter Liggett

Reading, PA · est. 1984

This Reading marker honors a soldier born here in 1857 who rose through the ranks after West Point to command troops in the Philippines and, in the closing weeks of World War I, to lead the American First Army in France. He took over that command from General John J. Pershing in October 1918, guiding it through the war's final offensives on the Western Front. He reached the rank of lieutenant general before his death in 1935.