A celebration of capitalism in Midtown.

Mysterious 500-year-old tapestries depict a unicorn hunt.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

A room in New York City that contains 250 cubic yards of dirt worth a million dollars.

A hands-on traveling collection of the innovative devices of yesteryear.

New York City's smallest piece of private property.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

Elevated freight railway turned wildly successful urban park.

Tucked in the back of this amazing antique store is an important piece of medical history.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

A museum of natural history, Edwin Carter's original log cabin home and workshop houses taxidermy specimens.

A lively annual event in which thousands of people race to push coffins heavy with bodies up a hill.

A stark reminder of the huge nuclear weapons plant that once stood on the site and its effect on the surrounding area.

The fifth-longest natural arch in the world, and the longest outside China.

The huge collection of paintings of the American West is one of Denver's best-kept secrets.

These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

The largest self-built castle in the U.S., six decades in the making.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

One of the world’s largest collections of petroglyphs records 2,000 years of human activity.

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

A house carved into a rock in the 1940s.

Bizarre lunar-like landscape with thousands of large stone "hoodoos."

Life-sized sculpture of a blue whale made of hand-recycled plastic trash.

One man’s passion for gas stations is on display along the Rio Grande in northern New Mexico.