Climb inside an iron crystal magnified 165 billion times its normal size.

An Albanian monument to the Communism that nearly crushed the country is now a crumbling wreck.

In the heart of Tirana, this underground nuclear bunker has been transformed into a museum.

A museum dedicated to secret surveillance.

What happens when you cross a mayor and a painter?

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

The elliptical citadel resisted the advance of the mighty Ottomans several times, thanks to the military prowess of the "Dragon of Albania."

This Renaissance palace features a unique architectural design and is now home to the Ferrara National Art Gallery.

Ozymandias’ time-keeping temple.

The largest known Ancient Egyptian obelisk.

One of its engravings is believed to be among the first representations of medical and surgical instruments.

These Egyptian statues have survived for 3,400 years and were an acoustic wonder of the ancient world.

The medieval center of the Islamic world was also once the seat of Saladin's sultanate.

This structure atop a craggy cliff in one of the most beautiful parks in Paris boasts an unbeatable view.

Order a boozy baba au rhum at the oldest patisserie in Paris.

A museum on the history of Paris, including a set of Napoleon's toiletries, Proust's room, and relics of the Revolution.

A museum dedicated to one of Paris’s most famous residents, tucked into a corner of one of the city’s most famous squares.

This bridge was constructed from the rubble of the infamous Bastille.

The remaining relics of the patroness of Paris lie in a chapel under a striking double spiral staircase.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

Site of a classic 19th-century physics experiment to prove the earth is rotating.

This Armenian monastery was carved out of cliffs and named after the spear used to stab Jesus.

A geological oddity topped with a 2,000-year-old pagan temple.

The most visited pilgrimage site in Armenia once held a saint in a pit for 13 years.