A walk through the historic city center, under the streets of Seattle.

Erosion and various mineral deposits give this striking canyon its distinct color and soft appearance.

This set of three large, volcanic hot springs is a favorite haunt for intrepid divers.

The extensive collection of an amateur naturalist.

A museum in rural Utah documents the history of the Japanese Americans who were forcibly relocated there.

Visitors to this library are in for a real-world education in modernist architecture.

A tunnel with windows, so you don't miss out on the impressive views.

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

Despite sitting firmly in the global cradle of the Church of Jesus Christ of Latter-day Saints, this Hare Krishna temple is host to one of the largest color festivals outside India.

Hundreds of drawings left by the land's previous inhabitants remain mysterious.

Largest collection of mounted dinosaur specimens in the world.

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

One of the world's oldest and most massive living organisms is a grove of quaking aspens.

Dig for your own trilobites in this goldmine of invertebrates.

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

This geothermal hot spring hides beneath a slowly growing mineral dome.

This 14th-century temple is also known as the "Temple of the Golden Pavilion" for its gorgeous gilded reliquary hall.

This ancient shrine has been rebuilt every 20 years since the eighth century.

Rows of stone statues are dressed up to mourn children that are lost before birth.

A sobering scientific reminder of the human damage caused by the advent of the nuclear age.

An anthropological theme park that depicts the cultures of around 20 different countries.

Devoted Buddhists can earn enlightenment in the next life by crawling through this symbolic nostril.

Thirty architectural gems from the 19th- and early 20th-century Tokyo were restored and relocated to this space.

The quintessential Japanese rock garden has existed for more than 500 years.