6. Money was tight. Though the Washington Monument Society solicited donations for a decade, it had trouble raising sufficient funds to build Robert Mill's elaborate design. Still, construction began on the Washington Monument in 1848 -- but was stalled again after a change in the Washington Monument Society's administration alienated donors and led to bankruptcy in 1855. According to the National Park Service, the monument stood partly finished for more than two decades, "doing more to embarrass the nation than honor its most important founding father."
7. When the monument officially opened in 1886, visitors had to climb 898 steps to reach the observation deck. After a short hiatus, the monument re-opened in 1888 with a public, steam-driven elevator, which made the trip to the top in just 10 to 12 minutes. However, it was considered too dangerous for women and children, who were prohibited from riding. The steam elevator was replaced by an electric elevator just 13 years later, in 1901. The ride now takes only about 70 seconds.
8. Three different types of stone were used to build the Washington Monument. After the first quarry used for the construction became unavailable, builders turned to a quarry in Massachusetts. But problems with the quality and color of the stone prompted builders to use stone purchased from a third quarry near Baltimore to complete the upper two-thirds of the monument. The colors of the three different quarries did not match perfectly, and the stripes caused by the changes are still visible today.
9. The monument weighs an estimated 100,000 tons -- and the pyramidon alone weighs 300 tons.
10. In 1982, a 66-year-old Navy veteran named Norman Mayer drove to the base of the structure and threatened to blow up the monument with 1,000 pounds of TNT unless government officials considered banning nuclear weapons. Several tourists were trapped inside the building, but were later released. The police eventually shot and killed Mayer but when they searched his car for the TNT, they found nothing.