Cooled, fractured lava formed this geometric rock feature.

The first privately-owned space capsule to orbit and land carried a secret payload: a wheel of Le Brouère.

This large pile of traveler-curated rocks by the dry lakebed is a longstanding tradition on the Old Mojave Road.

A volcanic tunnel illuminated by natural skylights offers a shaded respite from the desert sun.

The world's first permanently occupied mountain-top observatory continues to report on the stars.

This unique formation appears as though an asteroid landed on the forest.

An eatery within a Bay Area Buddhist temple pulls off all your favorite Vietnamese classics without the meat.

A performance hall at the American Jewish University moonlights as a sci-fi film location set.

A 70-foot replica of the famed Eiffel Tower.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.

This remote Colorado canyon is home to the second-largest collection of natural arches in the world.

A volcanic cone that formed over 600 years ago.

Deep vertical fissures like miniature slot canyons cut across the cemented volcanic rock of Black Point above Mono Lake.

The largest dinosaur trackway in North America is tucked away among this canyon's ghosts and archaeological gems.

A careful eye can find hundreds of dinosaur tracks running along the Connecticut River.

A beautiful red-faced slot canyon in northern New Mexico.

An institution dedicated to the towering buildings that make up skylines in New York City and around the world.

An old railroad grade built for the construction of Hoover Dam is now a recreational trail featuring several tunnels and sweeping views of Lake Mead.

A Norwegian-born sculptor created these soaring guardian angels at the entrance to Hoover Dam.

These markers are used to document elevation changes around the famed dam.

Once an ancient sea, this landscape of rocky ravines is filled with the fossils of ancient marine life.

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

Monument to a brutal, ineffectual US bombing campaign and a sobering reminder of the human cost of the Vietnam War.

Dyed by iron oxide over centuries, these sandstone rocks rise thousands of feet into the sky.