A wonderland of caves in eastern Iowa.

One of just a few cities in the world to base their center of government on an island. Others: Paris and Osaka.

Remnants of a quarry company town still stand on the banks of the Wapsipinicon River.

Elaborate hand-carved wooden clocks two brothers made in their spare time are on display at this handsome little museum.

Most comprehensive museum in America devoted to one ethnic group.

No one knows the origin of this small town’s unique name.

The “American Gothic" artist's largest works hang in an Iowa State University library.

An Iowa town celebrates its heritage with the tallest working Dutch windmill in North America.

Eight feet in diameter and more than 24 feet around.

This remote island in Iowa was abandoned after being devastated by flood.

A half-mile long and three stories high, this bridge over the Des Moines River Valley mimics a descent into a mine shaft.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

This English-inspired Maryland garden is home to acres of opulent plant life including bushes shaped into an entire fox hunt.

These buildings are a poignant reminder of the thousands of horses and mules who passed through this area of the Shenandoah Valley on their way to war.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

Rumors persist that a bottle of whiskey is sealed within this Demijohn-shaped adornment.

According to local history, this cast-iron canine was nearly melted down for bullets during the Civil War.

This three-story Victorian mansion is now home to the National Park Service’s Historic Preservation Training Center headquarters.

Unannounced visitors are now welcome at the site of the largest Prohibition-era bootlegging operation in the region.

The smallest covered bridge in Maryland.

First built around 1848, this bridge was destroyed by arson, but original timbers are included in the replacement.

Washed out by the Johnstown Flood in 1889, the surviving portion of the original two-span bridge now resides at Fishing Creek.

A well-preserved quarry and six of eight continuous burning pot kilns used to make burnt lime and crushed stone are highlights of the self-guided walking tour in Fountain Rock Park.

Take a trip to the past aboard a 1920s railcar or open flatcar for a scenic ride through Maryland farm country.