46. Metropolitan Museum of Art. 
Among the most visited museums in the World, the Metropolitan Museum of Art is the largest art museum in the US. It maintains an extensive collection of African, Asian, Byzantine, Indian, Oceanian, as well as Islamic art.
47. New Mexico’s Carlsbad Caverns. 
Located underneath the rugged ground of rocky slopes, shrubbery, and cactus is 118 caves forming the oldest cave systems in the world, the Carlsbad Caverns.
48. Nevada’s Hoover Dam. 
Formerly known as Boulder Dam, Nevada’s Hoover Dam is a concrete arch-gravity dam built in the Black Canyon of the Colorado River. Being more than 1,200 feet wide at the top, it is considered the largest dam in the world.
49. Abraham Lincoln Presidential Library and Museum. 
Experience the whole Abraham Lincoln story from the former US President’s humble beginnings to his days in the White House.
50. National Museum of Amerian History. 
The National Museum of American History presents the nation’s experience from colonial times to the present through the more than three million historical specimen and objects maintained on the site.
