Sofia's legislative center is continuously reinventing itself.

An underground world of gorgeous, palatial metro stations designed as a nuclear shelter complex.

According to Greek mythology, this natural spring is the home of a freshwater nymph.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

In one of the world's smallest countries, a royal's personal winery is open to the public.

Browse through a century of this principality's first popular export.

The kitsch mansion of the former Romanian president Nicolae Ceaușescu features a golden bathroom.

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

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

A scenic UNESCO site that doubles as a habitat for various forms of wildlife.

A curious little museum dedicated to the furry feline in the cat haven that is Old Town Kotor.

This historic electric train has operated with regularity since the early 1900s.

This enormous censer uses a pulley system installed over 400 years ago.

This local emblem is the oldest and largest dragon tree in the Canary Islands.

According to the Guanches, the aboriginal people of the Canary Islands, the king of evil lives inside this volcano.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

The oldest Roman lighthouse still in use.

An early 20th-century bullring converted into a modern shopping center.

Partially collapsed lava tube and cave system complete with concert hall, underground pond, and unique albino crabs.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

Dozens of elegant ceramic tiles decorate these ancient walls, each displaying the Lord's Prayer in a different language.

Squeezing inside this deep, narrow canyon reveals a festival of desert colors.