A miniature golf course crafted inside the world's largest simulated cave.

An otherwise quiet campground becomes a bustling medieval town for two weeks every year.

For decades, it has disappeared and reappeared as water levels rise and fall.

A hidden piece of Altoona's railroad history in a long-forgotten abandoned town.

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

Journey through a collection of over 35,000 Halloween items from all generations.

Pennsylvania's highest point is spotted with boulders which were pushed to the surface by nothing but cold.

A daily replay of the experiment that proved the rotation of the Earth.

A tradition unlike any other, this marks the site of the annual Groundhog's Day tradition.

One of the U.S. Forest Service's only mansions is outfitted with a dinner table for floating food.

Locals call this magical moss-covered walkway the "Emerald Path."

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

In the bowels of a 19th-century brewery lurks a fine-dining restaurant offering an array of themed feasts.

Erected in 1697 this Philadelphia bridge is the oldest surviving roadway bridge and perhaps the oldest stone bridge in the United States.

Behold the rickety wooden glory of the world's oldest operating roller coaster.

The home and studio of a visionary woodworker now stands as a museum and example of his artistic genius.

A local prank turned town icon.

It would take 35 firetrucks to fill this enormous glacial pothole.

This lush forest valley was once mined for lumber to the extent that it was once nicknamed "The Pennsylvania Desert."

The oldest farmer's market in America is so ancient it was approved by the King of England.

This hidden gem of a garden has one of the only surviving Victorian ferneries in America.

When the Austin Dam failed it destroyed much of Austin...and then it failed again.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

This Old Testament garden features 100 plants from biblical times.