Overview: The US capital boasts many memorials, but none with a more bizarre history than the obelisk erected to America's first president. Over 55 stories high and weighing over 90,000 tons, the Washington Monument stands stalwart in the city's center. From concept to completion, it took 100 years–years filled with mystery, ceremony, conflict, government action, and inaction. Proposed in the late 1700s by a group of prominent citizens and finished in the late 1800s by the Army Corps of Engineers, the exterior is mainly Maryland white marble, while the interior is made of granite, iron…and a few surprises. How did it come together and why did it take so long? Historians tell stories of stalling bureaucracy, secret societies, and triumphant engineering. Stark and daunting on the outside, we let viewers know what's inside.