Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A war-torn Olympic relic is being overtaken by graffiti and nature.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

Bridge that died in war and was resurected.

Once the fallout shelter of a dictator, this sprawling bunker is now a combined history museum and contemporary art gallery.

Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

2300-year-old Roman road connecting the empire.

This statue was given to France by the United States to commemorate the centennial of the French Revolution.

Mysterious 500-year-old tapestries depict a unicorn hunt.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

Elevated freight railway turned wildly successful urban park.

A monument celebrating the idea of reaching inaccessible places.

The world-record holder for the longest bridge stretching continuously over water.

Colombia's biggest botanical garden contains plants from all across the country.

This stone complex marks the urban center of a lost civilization.

This vast masterpiece of Moroccan architecture spreads across 20 acres.

Come for the flowers, stay for the bats!

The 953 windows undoubtedly make this the world's most beautiful screened porch.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

This opulent 16th-century Maharaja’s palace is a unique mix of Hindu and Muslim designs.

A blooming house of worship for the masses.

Whitewashed mosque contains the world's largest carpet.