The ancient heart of Tunis is an enormous maze of narrow streets and alleyways.

The final resting place of the liberator of Argentina is guarded around the clock by two soldiers.

A grotto replicating one of the world's most famed Marian apparitions sits across the ocean from the original.

This beautiful fountain was sculpted by a female artist who was ahead of her time.

A geological mystery on Camelback Mountain.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

This historic national park is covered in the stunning ruins of red rock pueblos.

Don't blink or you'll miss it.

The drama of nature in full effect in this Nevada State Park.

The most magnificent bottle house in a town strangely full of them.

Odd outsider art installations surround a Gold Rush-era ghost town.

Millions of years of oxidation make a drive down this winding Death Valley road surprisingly colorful.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

Space-age minarets towering over Islamabad.

One of the last surviving ancient Buddhist sites in the region, it escaped the brunt of several Hun invasions thanks to its remote location.

A 17th-century mosque that was used for war more than worship.

A mere stone's throw from Islamabad exists a spectacular display of three millennia of humanity's progress.

These stairs were built to accommodate royals mounted on elephants.

Road signs in Namibia mark the location of one of the five major circles of latitude.

Bizarre living fossil only grows in a small chunk of the Namib Desert.

Made famous by 'Star Wars,' these troglodyte homes face an uncertain future.

An ancient burial ground believed to have been used for ritual sacrifice.

Ancient barriers wrap around what was once an important stop along the Silk Road.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.