This triumphal 16th-century arched gateway leads to the oldest street in Palermo.

Why a column on the entrance is inscribed with a verse from the Quran is one of Sicily's many mysteries.

This mosaic-lined medieval church was built by the world's first admiral and still holds mass in ancient Greek.

A study of Fascist era Art Deco design in Italy.

An abandoned shopping gallery built during Fascist Italy tucked in the center of Palermo.

This is Bremen’s oldest historic district, famous for its labyrinth of narrow medieval alleys lined with tiny, colorful 15th-century houses that resemble beads on a rope.

A poet’s rustic cabin, rescued from demolition and tucked into Rock Creek’s greenery

The largest stretch of the Berlin Wall is right on top of the former SS headquarters

An elegant German-style resort overlooking the Potomoc River.

Gustave Eiffel's masterpiece until the Eiffel Tower was built.

An international border crossing near the famous Iguazú Falls where bargain hunters and curious tourists stream between Brazil and Paraguay.

When this 160-year-old church was being built, a stonemason included a hidden homage to his late daughter.

Unique fence hidden along multi-use trail near Pearl St and Mount Sanitas

This now-abandoned outcrop is an important Native American spiritual site, overtaken by European settlers and mining pollution.

The world's largest sticker ball weighs in at a mighty 231 pounds.

A coal fire has been burning underground here since 1896.

Oddly shaped rock formation, misassociated with a nearby utopian community.

A house carved into a rock in the 1940s.

This site is home to ancient petroglyphs and pictographs dating back to 6,000 B.C.

This Moab institution functions as both a rock store and a small natural history museum.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

No one knows exactly how deep the world’s deepest geothermal hot spring is.

This hot dog-shaped diner has moved all around Colorado, but has never been to New York.

This 28-foot-tall milk can contains one of the most whimsical ice cream parlors in town.