This advertisement for talcum powder was painted on the rock face and has since defied removal.

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

This shale formation along the Appalachian Trail once inspired the third president of the United States.

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

Time travel with sweets across history at this research-based candy store.

A former Confederate hospital serves as a remembrance of wounded and dead soldiers.

This museum devoted to the gothic author holds such interesting ephemera as his socks and walking stick.

Dedicated to the art and science of glass in equal measure, this space is as much laboratory as museum.

Curious crustaceans support an obelisk from ancient Egypt that now stands in modern-day Central Park.

A bit of retro transportation flair preserved in the world's largest department store.

The ruins of a Duke's bucolic dream, where camels once roamed alongside "Dutch" windmills and faux-Italian vineyards.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

A lovely aquatic park built by a one-armed Civil War veteran who made a fortune from lotuses.

One of the oldest of its kind.

Mural made of 100,000 pieces of hand blown glass, and one of the largest glass murals in the US.

The oldest active church in Pennsylvania is also the second oldest Swedish Church in the United States.

Step into a pastel time capsule where candy is truly dandy.

The world’s first penitentiary, meant to be humane, drove men insane.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

The first American department store, and home to the largest operating musical instrument in the world.

This lovely pocket park is one of the most under appreciated in D.C.

This lonely waterfront memorial to the men of the Titanic was erected by the "Women of America."

The Corinthian columns that towered over Abraham Lincoln’s inauguration stand proud.