A fascinating community art piece created by students, teachers, and noted Philadelphia artist Isaiah Zagar.

A tribute to those that perished during the American Revolution.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

A former plant in one of the hubs of U.S. steelmaking has been turned into this museum celebrating the history of American industry.

A park full of outsider art, created by college students studying outsider art.

Mysterious rocks that ring musically when struck.

Eccentric concrete mansion and museum designed and built by hand from the inside out.

Designed by Horace Trumbauer in 1893, this Gothic-style castle is now a home for academics.

Frank Lloyd Wright built this suburban synagogue late in life, but it stands among his most iconic masterpieces.

This meticulously extracted nervous system allegedly came from a 19th-century custodian who donated her body to science.

The oldest surviving presidential residence in the United States.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

This hidden gem of a garden has one of the only surviving Victorian ferneries in America.

The oldest surviving botanic garden in the United States.

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.

One of the oldest log cabins in America is one of the last of its kind this historic Swedish dwelling remains a piece of living history.

This little-known Revolutionary War fort is supposedly haunted by the ghosts of its past.

A beloved horticultural oasis on the grounds of a wealthy family's former estate.

This might just be the TARDIS of bookstores.

The home and studio of a visionary woodworker now stands as a museum and example of his artistic genius.

This historic old movie house was the scene of one of the Blob's most iconic attacks.

The headquarters of the Fraternitas Rosae Crucis, complete with Rosicrucian pyramids, all in the Pennsylvania woods.

A "house to which to flee" for settlers in colonial Pennsylvania.

This roadside stand packs 300-plus varieties of tomatoes, from "Maiden's Fire" to "Kaleidoscopic Jewel."