This plaque celebrates the sister city relationship between Fredricksburg and Fréjus.

On the upper deck of this church-owned parking garage stand eight pillars topped with different Catholic saints.

An industrial waste tourist attraction.

The so-called "Father of Las Vegas" had the city's first telephone installed in his office in 1907.

Dedicated to the explorer who opened Japan to the West.

The only statue of its kind to commemorate Washington's beginnings as an officer of the British Colonial Militia.

A daily replay of the experiment that proved the rotation of the Earth.

The humble field where the first Major League Baseball game was played.

An eccentric priest's tribute to George Washington, this chapel tells the story of the American Revolution.

This restored log building was one of the first toll booths for travelers along the Northern Turnpike.

The oldest house in Washington, D.C. wasn't originally constructed in the nation's capital.

Also known as the Founding Church of Scientology.

A public art jibe at one of the United States’ oldest and longest-serving senators.

This apartment building designed by a notable Washington D.C. architect housed the Qing Dynasty's Legation.

A hidden passageway now marks the site of an assassination attempt on Ronald Reagan that some say broke a 140-year-old curse.

You could be standing at the site of one of D.C.'s most fatal tragedies and not even know it.

Named after an outlaw who used the basin as a hideout.

This sign designates the road that leads to the infamous Area 51.

These markers are used to determine the ground stability of the Strip.

An overlooked memorial honoring the local Washington residents who died in World War I.

These markers are used to document elevation changes around the famed dam.

A "house to which to flee" for settlers in colonial Pennsylvania.

The oldest surviving presidential residence in the United States.

Designed by Horace Trumbauer in 1893, this Gothic-style castle is now a home for academics.