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

This titanic oil company sign is a reminder of the Americana boom of the 1970s and also its commoditization.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

A chessmaster's dream destination.

Less a museum than a bizarre fantasy world created by artists and engineers.

The only castle in North America to ever house European sovereigns.

A museum in the former home of Marxist revolutionary Leon Trotsky.

Frida Kahlo's childhood home, now a museum of her life and works.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

A bright little alley in La Boca is a part of tango history.

105-foot wide giant metallic flower blooms anew every day in the heart of Buenos Aires.

Buenos Aires' city of the dead contains some very famous remains, including Eva Perón.

This historic, palatial theater is now one of the world’s most beautiful bookstores.

Massive rock sculptures formed during the time of the dinosaurs still stand undisturbed.

An ancient forest of the Paleocene Age turned to stone.

Stenciled handprints and wall paintings dating back 10,000 years, some of the earliest forms of cave art.

The inspiration for the Patagonia Clothing logo, Cerro Fitz Roy turns pink at sunrise.

This stunning mass of ice spans 121 square miles and is still growing.