Unisphere

New York, NY

This plaque marks the room in Manhattan's Hotel New Yorker where Nikola Tesla, the visionary Serbian-American inventor, spent his final years and died alone in January 1943. Decades earlier Tesla had helped win the 'War of the Currents,' championing the alternating-current systems that made it practical to transmit electricity across long distances and light entire cities. By the time he died in near-poverty, the AC power grids he pioneered had become the invisible backbone of modern life. The marker turns an ordinary hotel address into the last chapter of one of history's great inventive minds.

Village of Irvington, NY

In an age when a message could only cross the ocean as fast as a ship could carry it, the New York financier Cyrus W. Field spent years and several heartbreaking failures trying to lay a telegraph cable across the floor of the Atlantic. His persistence paid off in 1866, when a working line finally linked North America and Europe and let words leap between continents in minutes rather than weeks. Field made his home in the Hudson River village of Irvington, which honored its most famous resident by naming this road for him and dedicating it in December 1931.

Atlantic Highlands, NJ

In the 1890s, self-taught inventor Simon Lake was racing to prove that a boat could travel and work along the ocean floor, not just dive beneath the surface. His first effort, the Argonaut Jr., was a modest hand-cranked craft he built and tested in the waters off Atlantic Highlands, launching it in the harbor in 1895. Crude as it was, it validated Lake's ideas about wheeled, bottom-crawling submersibles and set him on the path to the larger Argonaut and a long career as a rival to fellow submarine pioneer John Holland. The vessel standing here today is a full-size replica, rebuilt in 1994 by the Atlantic Highlands Lions Club to honor that local chapter of American invention.

Greenwich, CT

In the winter of 1921, radio was still a young and unruly science, and most experts believed the long waves were the only way to reach across oceans—leaving the crowded short waves to amateurs. On December 11 of that year, a small experimental station built by members of the Radio Club of America transmitted from this corner of Greenwich and was heard clear across the Atlantic in Ardrossan, Scotland. The feat proved that short waves, far from being useless, could carry signals immense distances with modest power.