A natural gas leak provides a flickering flame beneath a waterfall.

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

Two mammoth statues inspired by equally tall tales lure tourists to this roadside attraction.

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

This splendid Versailles-inspired mansion has the largest French-style formal gardens in North America.

A desiccated merman and a walrus penis bone are among the oddities in this eclectic collection of shipwreck treasures.

Current docking place of the SS United States, the fastest transatlantic ocean liner.

These lush botanical gardens employ the most purrfect pest control force.

A toxic ghost town sitting atop a massive coal fire.

World's first "penitentiary," meant to be humane, drove men insane.

Yo, Adrian!

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

This might just be the TARDIS of bookstores.

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.

This weeping, 10-foot-tall sculpture was a maquette for a 9/11 memorial.

This local gem houses the largest collection of pre-Raphaelite paintings outside of the U.K.

A grotesque Fiji merman dwells within this traditional Dutch-style building.