A pyramid commemorates the birthplace of James Buchanan, the 15th president of the United States

Lines from a walking song are etched into a rock in Natural Bridge State Park.

The eerie ruins of a remote abandoned hamlet said to be founded by the survivors of a shipwreck.

According to local lore, this narrow passageway through two large rocks was accidentally created by the devil himself.

Located within a historic park, the beacon is the oldest standing structure in Miami.

This beautiful ancient site is dotted with perforated sandstone pillars considered sacred by some Native American groups.

An abandoned network of military bunkers and tunnels open for anyone willing to descend into the darkness.

Foragers once flocked to this big beautiful bayou to hunt for pearls.

Over 100 million years ago, beach-bound dinosaurs left permanent marks on San Antonio's landscape.

World War II-era bunkers are hidden under the beaches of this picturesque park, which is still scattered with wartime watchtowers.

A raised boardwalk winds through a thicket of stunted, century-old trees no more than nine feet tall.

At this Minnesota state park you can easily wade across the source of the mighty Mississippi.

The lowest point in the state of Illinois, at the confluence of the Mississippi and Ohio rivers.

One of America's first planned communities is preserved in a state park.

A historic blockhouse and trading post give a glimpse into the early colonial history of South Carolina.

This Florida sinkhole hides a rainforest-like micro-environment in its depths.

Bizarre lunar-like landscape with thousands of large stone "hoodoos."

Bad farming practices caused this unnatural natural wonder.

A remote desert lookout offers unparalleled views of the California badlands for those who brave the trek.

Rising out of miles of farmland, these buttes are sometimes called the world's smallest mountain range.

This quiet park's strange sedimentary spires were named after Kodak's color film.

Moonbows over Kentucky.

This scenic Maryland park was the site of one of the worst prison camps of the Civil War.

The scant remains of an expansive indigenous civilization can be seen at this Arkansas state park.