The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

The first memorial dedicated solely to the Black troops who fought for the Union.

"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”

The preamble to the U.S. Constitution written entirely from vanity license plates hangs in the Smithsonian museum.

Art deco landmark on the outskirts of Washington, D.C.

Perhaps the most scandalous statue of America's first president.

The famous abolitionist’s preserved estate is one of Washington's finest monuments to its great Black citizens.

Largest Roman Catholic church in North America.

This lonely waterfront memorial to the men of the Titanic was erected by the "Women of America."

The winding route passes through an enclosed alleyway, two tunnels, and leads to the White House basement.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

Scattered throughout London are ancient remnants of the city's former bounding wall.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

An eerie reminder to the horrors of World War II.

Only the face remains of this giant Buddha statue, which is said to be a source of luck for students.

This enormous monument is one of the most iconic structures in Tokyo, rudely nicknamed "The Golden Turd."

Designed by a computer, this intricate network of fluorescent green pipes has taken over a subway station.

Take a few seconds to look at this abandoned, art-filled station as you pass by on the subway to Ueno.

Tragic reminders of the 1945 firebombing campaign over Tokyo still haunt this bridge.

An enormous pair of straw sandals woven in the traditional way—to keep demons at bay.

This 14th-century temple is also known as the "Temple of the Golden Pavilion" for its gorgeous gilded reliquary hall.

A calico cat named Tama was the wildly popular Super Station Master at this train stop in southeast Japan.