This monument built by Japanese American immigrants spent decades underground.

Now a pedestrian bridge, this was once part of a narrow-gauge railroad that ran along the east coast of Kauai.

Football field-sized microalgae production tanks on the Hawaiian coast create a stunning view from space.

A priest with no formal artistic training used basic house paint to create gorgeous religious scenes inside this historic church.

A controversial memorial at the place where Captain Cook met his violent end.

Try your hand at old-fashioned coffee growing at this museum devoted to one of the world's most coveted beans.

This unusual lava tube spouts seawater during high surf.

A cooled lava flow from the Haleakalā volcano formed these surreal-looking columnar basalt structures.

A true treehouse near Hawai'i Volcanoes National Park.

These ancient sacred grounds granted amnesty to those who managed to reach them.

This legendary urban waterfall creates a dazzling display of rainbows.

The island of Lanai in Hawai'i is a paradise for cats and cat lovers.

This black shoreline is made up of exploded lava particles.

A beach made of semi-precious green sand on the Big Island of Hawai'i.

Hide from the tourist hordes in these relatively unknown, and unguarded lava caves.

Watch the newest land on the planet form before your eyes.

These picturesque Hawaiian falls are home to a rare species of fish that uses a special sucker to climb up cliffs.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

Colorado's only true geyser is hidden within the San Juan National Forest.

A wealth of pop culture statuary and green chile dishes give this roadside restaurant clout.

Wee (and not so wee) footprints that insects and reptiles of the Paleozoic Era left behind.

A unique geological area spiked with wind-carved rocks that resemble teepees.

This quirky hot springs town known to locals as "T or C" was named after a radio show.

A small metropolis of Pueblo cave dwellings have been carved right into the hillside of this national monument.