A market built atop boats is one of the few floating holiday markets in Europe.

A well for a well, this anachronistically Indian-styled water pit was built in its small town home in gratitude for a similar favor.

On rare days, this abandoned castle's gatekeepers open its doors, revealing the eye-popping splendor hidden inside.

Holding the most bodies of any cemetery in the United States.

A hyper-luxurious, 12,000- square foot home might be buried beneath Queens, still waiting to protect you from nuclear missiles.

A uniquely lettered street sign marks the corner where the iconic word game was invented.

This mysterious marker puzzles pedestrians and infuriates geographers.

This Scottish castle has witnessed clan rivalries, Jacobite uprisings, whisky smuggling, and more.

The city of Palestrina was built around this magnificent terraced sanctuary dedicated to the pagan goddess Fortuna.

Moorish signal station on a stratgic rocky outcrop.

A giant Troll lurks under one of Seattle's oldest bridges.

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.

Amazing and mysterious Neolithic settlement on Scotland's Orkney Islands.

A battle between nature and architecture in the Cambodian jungle.

A beautiful Victorian-era cemetery, complete with a miniature village.

Pompeii's less famous neighbor is still revealing her secrets.

An island filled with hundreds of hanging, decomposing, decapitated dolls.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

This abandoned asylum was once a state of the art facility before devolving into one of the most deadly mental institutions in American history.

Ruins of a German Castle on top of a towering stone pillar.

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

These old stone ruins in the Oregon wilderness were once bathrooms and are steeped in legends of murder.