The highest point in Belgium is a staircase to nowhere.

A former ironworks that was the first UNESCO industrial site.

A treasure trove of Renaissance-era funerary art in a Roman church built on top of Nero's grave.

Breathtaking and huge 430 year old maps of Italy.

Secret refuge and museum of the Duke of Florence.

This 16th-century monastery has been turned into a surrealist architecture compound.

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

The world's second-tallest flagpole stands proud despite dropping rank.

This "tower of death" has acted as an observatory, a religious hub, and an executioner's lair.

Ancient barriers wrap around what was once an important stop along the Silk Road.

A fiery crater has been burning in the Karakum Desert since 1971.

Once a bustling fishing port, this semi-ghost town is now more than 90 miles away from the shore.

If you want to get married in the White Marble City of Ashgabat, you should do it in this surreal disco ball building.

A dictator's gold statue once rotated to face the sun on a 75-meter high marble tower.

Sumptous memorial to a controversial independence.

These little castles each held thousands of pigeons.

This ancient burial site is believed to be one of the first earthquake-protected structures in the world.

The ancient necropolis houses the immense rock-cut tombs of four Persian kings.

The palace of the King of Kings, burned by Alexander the Great.

This ancient subterranean megalopolis is known for the hot oil traps that were installed above each of its entrances.

While not Turkey's deepest underground city, this subterranean redoubt is the largest.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

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

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