A colorful public mural in San Antonio's West Side encourages students to stay in school.

This simple frog painting created by musician Daniel Johnston embodies the spirit of Austin.

The mummified relic of St. Antoninus.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

Portugal's National Pantheon has a history of curses, collapses and financial problems.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

Tucked away inside this concrete building is a church and its grand display of brutalist architecture.

This unassuming chapel in Portugal plays host to a ghoulish collection of bones.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

Thomas Jefferson's estate is home to hundreds of varieties of historic fruits and vegetables.

An eponymous directional signpost erected by the first president of the United States.

The most confusing clock in New York.

Once called Winthrop Park in 1889, home to a decidedly sexy tribute to the Monitor vs. Merrimac battle.

A decommissioned military complex that's now a modern industrial park.

A celebration of capitalism in Midtown.

Cryptic messages embedded in the New York City sidewalk.

New York City's smallest piece of private property.

Plot your trip through the city on the sidewalk.

Church in Manhattan holds the bloody sock of Padre Pio, among with many other unusual relics.

The last remnants of what was once one of the world's grandest hotels can now be found in a Manhattan subway station.

Manhattan's lighthouse, erected at the insistence of the unsinkable Molly Brown.