Follow the steps, and this roadside artwork will teach you how to dance.

Once decrepit and slated for demolition, now one of the longest pedestrian bridges in the world.

Wild lights and sound effects turn a walk through some caves into an eye-popping 1960s tourist attraction.

Designed by Buckminster Fuller, this relic of the 67 Expo survived fire and ice.

The deepest metro station in the world.

340-foot statue built to honour the Heroes of the Soviet Union.

A reconstructed medieval gateway that was the magnificent entrance to the capital city dating back to 1037.

Fragments of architectural wonders from around the globe are embedded in the newspaper building's walls.

All of Chicago's wood-paved streets are long gone but two alleys remain.

This $3 million model train takes you through Chicago, Seattle, and the thousands of miles in between.

Each of these gorgeous, intricately decorated rooms is painstakingly crafted to the scale of 1 inch: 1 foot.

The last masonry skyscraper ever built reveals a transitional moment in architectural history.

An outdoor urban gallery of large-scale artworks by the world's most influential street artists.

This surprising gem is a world-class archeological museum hidden at the University of Chicago.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

A science teacher's dream.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

This former maximum-security prison is creepy, sobering, and supposedly haunted.

A crumbling hospital from the 1850s on Roosevelt Island.

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

This automated sculpture of two men peeing will spell out text messages with their micturition.

A magical sinkhole on the Yucatán Peninsula is adorned with mini waterfalls and hanging vines.

Every equinox this Maya pyramid puts on a spooky ancient light show.

The most famous location in China was home to whole dynasties worth of imperial rulers.