Central America's deepest lake is actually a volcanic caldera, surrounded by three volcanoes.

Charnel house at the foot of Mount Sinai.

Traditional 11th-century outdoor tannery.

God's Saharan sandbox of wrath.

Vast stretch of tide-pools with a unique Moroccan charm.

An awe-inspiring mosque in Morocco with one of the tallest minarets in the world.

One of the most spectacular canyons in the world.

A monument to the defenders of the Arctic in Murmansk, Russia.

An ancient capital city that dates back 3,000 years and harbors many surprises.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

Giant topiary dog once played a role in a terrorist bomb plot.

Famously misunderstood wonder of the ancient world

A massive underwater sinkhole made famous by Jacques Cousteau.

Stalin's secret bunker.

Cold war icon and onetime "hole" in the iron curtain.

A marvel of Byzantine engineering under the streets of Istanbul.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

340-foot statue built to honour the Heroes of the Soviet Union.

This 1000 year old relic-filled cave monastery and UNESCO World Heritage Site also hosts an amazing micro-miniature museum.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

England's most notorious suicide spot.

Gargoyle head that brings good luck.

Hundreds of Buddhas in a re-discovered Indonesian temple.

Hindu temple of the dead home to hundreds of long-tailed macaques.