Free public park and gardens filled with peacocks and peahens.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

Neglected resting place of some of the city's early luminaries—and a woman encased in concrete.

America's only city hall with minarets took architectural cues from Ali Baba and the Forty Thieves.

A community of collapsing homes more than a mile out from the Florida coast.

An abandoned water sports stadium that has become a haven for graffiti and decay.

This beautiful Miami garden was designed as a laboratory for tropical plants.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

12,000 sq. ft. museum tracing erotic art from antiquity to modern times.

St Bernard de Clairvaux Episcopal Church, better known as one of the oldest European buildings in the Western Hemisphere.

An underwater city for the dead.

Old neon signs from the City of Brotherly Love provide a snapshot of the city’s evolution.

Hidden behind West Philadelphia rowhomes is a haven for migratory and local bird species both ordinary and rare.

The world's third-largest crystal sphere has sat in the Penn Museum since 1927 with the exception of one outlandish theft.

A tiny, unmarked beer and whiskey bar above an Ethiopian restaurant in West Philly fails to conceal live bluegrass.

This Philly landmark has a giant butterfly pavilion, three floors of insect displays, and withstood a $40,000 heist.

The abandoned coal loading dock is a canvas for unsanctioned art.

Remants of foundations, streets, and streetcar tracks inhabit the cliffs where a landslide occurred in 1929.

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

People escaping slavery may have hidden inside a corpse vault.

A wondrous old library overlooking the nation's capital.

An Industrial Revolution-era public work that purified water using nothing but sand.

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.