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

The oldest housing complex in Riga is a mini timeline of architectural trends.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

A small part of Russia that does not touch any other part of Russia.

A narrow strip of land is home to the tallest migrating dunes in Europe.

This Ukranian fortress is one of the best-preserved medieval castles in Europe.

The final resting place of soldiers' loyal canine companions.

360° views of the city plus five floors of optical illusions and hands-on science.

"Stairs of the Turks", a chalky white cliff eroded conveniently into stairs, allowing for easy pillaging.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

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

This triumphal 16th-century arched gateway leads to the oldest street in Palermo.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

Monasteries on rock pillars, once accessible only by frayed ropes.

This ominous Albanian fortress houses tanks and downed planes as a reminder of their victories over Western imperialism.

A medieval bridge stretches over a sulfur-rich river that leads to year-round natural hot springs.

In Northeastern Iceland lies something of an oxymoron: a steaming desert.

The bright red stripes streaking across the rocks are the star feature at this Icelandic waterfall.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

Three columns of volcanic rock shoot out of the ocean.

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

Medicinal spa created with the discharge from a geothermal energy plant.

Walk in the footsteps of the gods and straddle two tectonic plates.

An encyclopedic collection of mammal penises.