The ghostly remains of an accidental sea.

A monument to a one-legged kidnapper, horse thief, and charlatan asks visitors to throw rocks in a pile.

This dark, quiet forest on the outskirts of San Diego is dense with rumor and lore.

A dramatic coastline that’s home to a rare pine tree.

A blast from the past in central San Diego.

Not truly a ship nor a building, the Navy's first and last "landship" is now abandoned due to clerical issues.

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

A sculpture of the famous photograph stands on San Diego's "Greatest Generation Walk."

The world’s oldest active sailing ship.

An inconspicuous footbridge beloved by San Diego locals.

The freeway that never was.

Oregon's only closed-basin hypersaline lake, an important stopover for migrating waterfowl, is in danger of drying up completely.

An old copper mine in Plumas National Forest, formerly served by a tramway, seems to have been successfully remediated after years of acrimony and effort

A public fountain that spouts "health water" from a nearby spring.

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

This Nevada lake holds its titular natural pyramid and, if the legends are true, a number of dangerous spirits.

A desert ghost town—occupied for only 12 years—was once home to more than 500 silver mines.

Ancient human, animal, and geometric figures drawn in the earth.

Australia's largest collection of rare and bizarre insects.

An opal mining town in the middle of Australia where people live, worship, and shop underground.

A spectacular impact crater in the rugged heart of Central Australia.

Look closely and you’ll notice that the color changes a third of the way up the tower.

One of the largest fleets of armored vehicles in the world, sitting out in the California desert.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.