The only Florida state park with publicly accessible caves.

This ancient sinkhole-turned-healing-pool is a treasure trove of archeological discoveries and may even be the Fountain of Youth.

A gleaming white tower in ornate Indian style soars above the low-slung bungalows of north Tampa.

A hidden beach at the end of a tunnel of mangrove trees.

The ruins of this antebellum sugar plantation are the end result of a Seminole attack during the Florida Wars of 1836.

An abandoned vacation home spent a decade taking on legends. It's now taking on water.

Where manatees are the snowbird vacationers in these balmy Florida springs.

This Boston medical museum features the skull of the famous medical case of Phineas Gage.

Clusters of abandoned buildings hint at the facility's 144-year history with psychiatric health.

No one really knows how these old hobby horses got here, but the herd keeps growing.

A museum dedicated to the quirky and colorful world created by Springfield's favorite son.

Three prestigious academic collections come together to create a world-class natural history museum.

The often-overlooked ruins of one of the first buildings designed by famous landscape architect Frederick Olmsted.

One of the most scenic falls in Massachusetts has a history of death and grim legend.

The walkable ruins of an 19th century hotel, destroyed in a horse cremation gone wrong.

A collection of full-size movie monsters opened to the public.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

Two thousand artifacts from around the world collected by one woman who loved to travel.

This historic railway museum may have lost its passengers but not its love for trains.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

Finally, you don't have to be a pious Swedish seaman to relax like one.

Once the world's largest reinforced concrete structure, this abandoned bridge now beckons urban explorers.

Now abandoned, the first public health hospital in the U.S. saw more than one million immigrants from around the world.

One man's lifelong obsession with death.