If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

Architectural monsters are devouring this palace's every door and window.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

An alchemist's "magic door" stands in the middle of a Roman park.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

This subterranean necropolis holds three floors of antler-dug grave caves.

Stone Age solar temple is aligned with the sun on each equinox and solstice.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Every equinox this Maya pyramid puts on a spooky ancient light show.

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

A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

The most famous location in China was home to whole dynasties worth of imperial rulers.

This huge concrete map of Scotland was built as a thank you gift from a Polish soldier.

Ancient serpentine sacrifice holder that has stood the test of time.

A fountain standing as a testament to a doomed alliance.

1513 Turkish world map, full of European state secrets and snarky commentary.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

A marvel of Byzantine engineering under the streets of Istanbul.