A focal point of in Denver’s skyline for over a century, inspired by a Venetian basilica.

Overlooking the Colorado Convention Center is this giant sculpture made from thousands of triangles.

The video game-themed street art first popped up in the French city.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

Ancient serpentine sacrifice holder that has stood the test of time.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

The Grand Mall in Varna hosts one of the biggest collections of Soviet-era paraphernalia in Bulgaria.

This ancient theater, restored in the 20th century, lives on as a venue for dramatic and musical performances.

"Holy Wisdom" overlooks the city that became its namesake.

Sofia's legislative center is continuously reinventing itself.

This building has two facades of clashing architectural designs.

A striking symbol of the Bulgarian capital.

A Bulgarian monument to Russia's role in World War II is constantly being painted in pop culture protest.

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

This historic black and white monastery is one of Bulgaria's architectural jewels.

The temple that withstood the Nazis.

These abundant, over-the-top monuments are so widely scattered that they define the entire compact capital cityscape, often leading to jokes about whether there are more statues than residents.

This fortress dates back to the 6th century and is also the site of a controversial abandoned restoration project.

An unfinished Serbian Orthodox church with 1,389 golden crosses planned to represent the Battle of Kosovo.

A 11-foot former president stands on a Kosovo street that also bears his name.

This massive monument was unveiled the day Kosovo declared independence from Serbia.

A futuristic, brutalist masterpiece that is also strangely prison-like.

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

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.