These constructed wetlands naturally filter millions of gallons of treated wastewater every day.

A spiritual vortex among the red rocks in Sedona.

This concert pavilion on the shore of the Great Salt Lake has been destroyed by fire, water, and disinterest but keeps coming back.

This natural wonder is disappearing at an alarming rate.

A sealed test tube said to hold Thomas Edison's dying breath was given to the inventor's friend and mentee, Henry Ford.

The 80-foot tire that looms over Michigan's I-94 was once a Ferris wheel in the New York World Fair.

This national park on the shore of Lake Michigan features remarkable dunes that lie at the heart of a Chippewa legend.

The crown jewel of the Queens Museum is a nearly 10,000-square-foot architectural model of the city originally built for the 1964 World's Fair.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

The record holder for the world’s largest peach.

A bronze statue on a downtown corner honors Minneapolis's favorite career gal.

The secret city built by the Manhattan Project.

A perfect circle of twenty-four mysterious holes dates back to prehistoric time.

Japanese gardens dedicated to the Japanese farmer that refused to throw in the trowel.

She stares out across six lanes of traffic, clutching a musket and infant with determination.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

Settled by the Church of Jesus Christ of Latter-day Saints in 1859, this abandoned frontier town has appeared in several films.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

These giant metal horses graze on a hilltop near the Montana highway.

This museum glorifies the humble potato.

Sweet Willy, at 30 feet tall, is the world's biggest beagle.

Home to the deepest rift anywhere on Earth.

Turns out you can see the world without ever leaving Maine.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.