This island castle contains enough secret passageways to support a season of Scooby-Doo episodes.

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

Some North Carolina Cherokee have been keeping their history alive for decades with a single play.

The highest point in Tennessee, Clingmans Dome bears witness to the ravages of one type of insect.

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

The Grand Ole Opry's big voice came from a small home in rural Virginia where she was eventually buried.

One of the only memorials dedicated to journalists who died in combat.

Built in the 1850s, this church was of the first five churches constructed in Harper's Ferry.

The last holdout of a pre-Civil War rebel who took the matter of slavery into his own hands.

Bizarre Cavern.

A labor of love built by local hang-gliding enthusiasts, this ideal launch spot was outlawed by the authorities and has since been largely abandoned.

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

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

A pre-Industrial Age iron furnace and the site of a nearly-forgotten piece of Black history.

A Civil War Museum with some notable medical antiques.

A toxic ghost town sitting atop a massive coal fire.

The oldest farmer's market in America is so ancient it was approved by the King of England.

An unusual manor of stunning beauty, born out of a crippling disease.

Traveling this mountain pass reveals quaint stone buildings, stunning Irish scenery, and a bridge said to grant wishes.

A stunning Victorian abbey and walled garden on a lakefront.

One of Ireland's most infamous prisons for rebels including men, women and children.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

A museum marks and documents the site of the Titanic's launch.

Northern Ireland's Brobdingnagian stepping stones.