Tucked behind New Jersey's abandoned Gingerbread Castle lie the eerie ruins of a once-flourishing paper mill.

A completely round house designed for the Atomic Age.

This hospital fell into ruins after failing to act as the advocate for the mentally ill it was designed to be.

This palatial botanical garden is home to one of the largest pipe organs ever installed in a private residence, and a piece of Wood's cycad.

One of the oldest of its kind.

A layered tribute to the work of mosaicist Isaiah Zagar.

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

Huge masonic hall in Philadelphia with lavishly themed rooms.

This elaborate towering structure was once famed for its revolutionary height.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

What looks like a simple quaint estate in rural Pennsylvania was in the 18th century home to a small monastic community.

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.

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

The final resting place of many of New Jersey's most famous residents, including U.S. history's most in-vogue antagonist, Aaron Burr.

This colonial mansion has been home to a staggering number of American historic figures.

This Philly cemetery is the eternal home of many famous area residents, including Rocky Balboa's wife.

This stone tower marks a lookout point over the historic Washington Crossing, and maybe some buried treasure.

This demolished goliath of American industry once loomed over the depressed town it once made thrive.

A modern ghost town whose inhabitants were driven away by the growth of nuclear power.

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

An ideal wedding spot that is almost too ideal.

A field of nothing but boulders which resembles a giant's gravel driveway.

The famous bell was secreted away and hidden in a church in Allentown during the British occupation of Philadelphia.

A train station that was abandoned by the coal industry and was later converted into a cocktail bar.