A former Catholic seminary, now a Washington State Park, preserves undeveloped lands on Lake Washington and also hosts a luxury hotel.

Little is left of this formerly bustling railroad junction on the Transcontinental Railroad.

In the high desert east of Bend, the University of Oregon maintains a research observatory on a remote mountain peak.

An unusual double cinder cone with a bent oval crater, in the Lunar Crater Volcanic Field.

The ruins of a failed dam that was built over land later described as a "sponge."

Some 46,000 years ago, a volcanic eruption led to a flooding event that carved this short canyon with steep vertical walls.

Much of the spectacular canyon followed over a century ago by the Los Angeles & Salt Lake railroad is now accessible to cars.

These wave-cut overhangs on ancient Lake Chewaucan contain some of the oldest evidence of human habitation in North America.

This Idaho state park boasts the tallest single-structured sand dune in North America.

A history of the U.S. military, with a focus on Pennsylvania's contributions.

Pleistocene megafauna fossils are the subject of Nevada's newest state park at the northern edge of the Las Vegas metropolitan area.

The rocks exposed at Valley of Fire State Park also occur in a much less known but equally spectacular area a few miles to the southwest.

An isolated early 20th-century gold mine in the remote Pine Forest Range contains much preserved equipment.

An improbable sinkhole in the sediments flanking the Beaver Dam Mountains.

The "Grand Canyon of Southwestern Idaho" makes a spectacular gash across the flat Snake River plain.

Rocky outcrops containing overhangs, caves, fissures, clefts, and alcoves that invite exploration and scrambling.

The remote graves of a Scottish family who died of thirst while attempting to reach St. George.

Two geologically young and nearly circular volcanic subsidence craters, each about a half-mile in diameter, abruptly break the nearly featureless Snake River Plain.

This museum focuses on the history and culture of the German settlers in Pennsylvania.

A mining camp built around an unexpected occurrence of silver.

This dry lake bed was once an emergency landing strip for military and experimental aircraft.

A spectacular slot canyon at the northern edge of Lake Mead National Recreation Area.

A remote trail traverses the little-known Gearhart Mountains of southern Oregon.

The sump of the landlocked Carson River is a haven for wildlife.