Tour the world's largest deep-hole dimension granite quarry, where you can view the plant where gravestones are made and roll a ball down the outdoor granite bowling alley.

This naturally heated mountainous creek has created a group of neon blue pools of potentially deadly boiling water.

A spiritual retreat in the heart of Los Angeles offers stunning gardens and a labyrinth to lose yourself in.

This lake in the Cascades lives up to its name, disappearing down a hole every spring.

The oldest surviving synagogue in New York City is now a soaring art space.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

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

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

One man's extraordinary topiary garden in a small South Carolina town.

A French chateau, failed utopian community, odd museum, and Stonehenge replica in rural Washington State.

This naturally-sourced hot spring is now home to a clothing-optional resort.

Visit this playground of waterfalls, caves and sinkholes.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

A futuristic temple of light uses prisms and rainbows to create an atmosphere of peace.

Half of a waterfall goes into the river while the other half seems to disappear.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

The artist James Turrell is repurposing an extinct volcano crater as an observatory to experience the cosmos.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

Sandstone rock formations that look like they belong on the cover of a progressive rock album.

A huge musical sculpture and other art installations on the National Oceanic and Atmospheric Administration grounds.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

A waterfall 600 ft. inside a mountain, once the bane of gold miners, is now a spectacle of nature.