The defense built to protect one of the last found pieces of land on Earth.

This ancient structure is widely thought to be the oldest intact pyramid in the world.

The medieval center of the Islamic world was also once the seat of Saladin's sultanate.

A strange aquarium with stuffed fish, and almost no water for them to swim in.

Standing atop 2nd-century Roman ruins, this church is one of the oldest and most iconic in Old Cairo.

This historic cemetery is home to the largest private mausoleum in Europe.

This floating sculpture of ice is a poignant reminder of nature's power.

This handsomely carved wooden church is more than 800 years old.

Housing the famous Norwegian ice-defying 19th century polar exploration ship.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

The world's northernmost aquarium looks like it has fallen over.

A favorite with sightseers and locals alike, this Norwegian funicular provides easy access to a stunning view of Bergen and its environs.

Legend says these colorful, invasive residents are the descendants of birds released by Jimi Hendrix.

An architectural oddity hides in plain sight on this iconic London bridge.

This home on a quiet suburban street is completely covered with vibrant mosaics.

This pub was 238 years old when it decided to revamp its image: It started serving Thai food.

Eighty million natural history specimens call this gargantuan museum home.

At night, bats patrol this magnificent 18th-century space in search of book-eating pests.

The extravagance of Portugal’s "Pink Palace" resulted in a noble title being awarded to its owner.

A never-finished memorial to the heroes of the Napoleonic War has become "Scotland's Folly."

This renovated Art Nouveau bathroom from 1905 is worth the price of admission.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.