Nestled in the heart of San Francisco’s bustling Financial District stands a unique homage to the Mayan and Beaux Arts.

The remains of a ruined mansion memorialize the 1906 earthquake.

Tiki luxury on Nob Hill.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

A winding path built in secret on the edge of the continent.

An artsy hidden staircase leads to breathtaking views of San Francisco.

Faceless white figures loom over the city from the rooftop.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

What appears to be a wizard's lair in Milwaukee actually houses a massive water pipe.

A wonderfully curated used bookstore in an airport.

This extravagant Art Nouveau rest stop features a million-dollar view of the Columbia River.

A sculpture of a salmon swimming through a brick building.

Outstanding, eerie frescoes and decorations fill this 19th-century monastery.

This massive stone and steel monument remembers a century-old battle that cost thousands of lives and nearly destroyed the city.

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

This once-grandiose behemoth of a monument from the socialist era now sits quiet and closed up.

This massive concrete sculpture is said to be the heaviest communist monument on Earth.

An abandoned saucer-shaped monument in the Bulgarian mountains.

A striking symbol of the Bulgarian capital.

Sofia's legislative center is continuously reinventing itself.

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

A collection of art from Bulgaria's time as a communist state.

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