The walls and streets of the ancient city are peppered with penises.

Beautiful views and Roman-style statues on the Italian coast.

This clifftop arch is a natural stunner.

For decades, Puerta del Sol has been illuminated by a giant, guitar-wielding bottle of sherry.

A towering monument in Spain has proven to be more labor-intensive than initially planned.

Five million people are laid to rest here, more than the population of Madrid itself.

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

A lush indoor jungle fills this bustling Madrid transportation hub.

The world's largest sundial can cast a shadow more than 1,600 feet long.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

This ancient market is often referred to as the oldest shopping mall in the world.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Massive, unfinished broadcasting station stands as a monument to the fall of communism.

A gigantic statue of a Russian soldier watches over the ancient city of Plovdiv, a prominent reminder of the Soviet period in Bulgaria.

A vast Communist-era exhibition space in the Bulgarian capital.

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

A magnificent, glittering building tucked into a tiny Bulgarian mountain town.

A flamboyant five-story building in Bulgaria resembles a crawling snail.

An ancient Thracian city where fire rituals were practiced on the largest cult altar in Southeast Europe.

The site of many battles and tragedies, including the 40 maidens who leapt into the sea.

An industrial relic is now one of Europe's most staggering art spaces.

This massive steel pyramid can be entered by a set of jagged steps that let visitors stand in its heart.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

This temple to the sturm and drang of Richard Wagner contains a dragon's cave and reptile zoo full of living "dragons."