Sail through this subterranean show cave that is home to a legend that would go on to name nearly everything around it.

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

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

A museum dedicated to the strange and extravagant costumes and memorabilia of the mummers, a tradition older than Philadelphia itself.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

An Irish Memorial commemorating those who perished due to potato blight.

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

Dr Barnes' $25 billion private collection of art and arboretum.

Century-old shop, specializing in Occult products.

The last of Philadelphia's wood-paved streets is now a landmark of terrible engineering.

America's most famous piece of self-built architecture.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

A toxic ghost town sitting atop a massive coal fire.

The first American department store, and home to the largest operating musical instrument in the world.

Northern Ireland's Brobdingnagian stepping stones.

A layered tribute to the work of mosaicist Isaiah Zagar.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

I-95's Tijuana-style celebration of kitsch at the Carolina border.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

The world's longest known cave system.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.