Knowlton

Bryn Athyn, PA · est. 1972

In 1924 aviation pioneer Harold F. Pitcairn established his first flying field on this site, launching decades of experimentation in flight. He and his associates developed the American autogiro—an aircraft with a free-spinning rotor that pointed toward the eventual helicopter—and won the prestigious 1930 Collier Trophy for the achievement. This quiet Montgomery County ground was an early laboratory of American aeronautical innovation.

Springfield Township, PA · est. 2006

On this site in the late 1930s, Philo T. Farnsworth ran experimental station W3XPF, conducting some of the earliest live local television broadcasts. Farnsworth had pioneered the all-electronic television system, and his relentless work in electronics earned him a long list of patents. He was later inducted into the National Inventors Hall of Fame.

Philadelphia, PA

David Rittenhouse (1732–1796) was one of early America's foremost men of science — an astronomer, clockmaker, and instrument builder who won fame for observing the 1769 transit of Venus and later served as the first director of the United States Mint. This sundial marks the site of his birth and honors his mastery of astronomy and horology, the precise measurement of time. A self-taught Pennsylvanian, he embodied the Enlightenment ideal of the patriot-scientist.

Philadelphia, PA · est. 1991

In 1690 William Rittenhouse, the first Mennonite minister in America, built the English colonies' first paper mill along the Wissahickon Creek. Generations of his family expanded the operation, turning this valley into the birthplace of American papermaking. By the 1850s the village had grown to more than forty buildings, seven of which still survive from this once-thriving industrial hamlet. It was also the birthplace, in 1732, of the noted astronomer and instrument-maker David Rittenhouse.