The world's only statue dedicated to the greatest Great Dane in comic strip history.

This quarter-mile tunnel under the Bluff in Pittsburgh bends at a 45-degree angle.

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

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

This collection honors the iconic, and proudly American lighter that just won't quit.

The site where nine miners were trapped underground for over 77 hours in 2002.

World's largest Christmas store.

A charming remnant of 19th-century fishing towns sits on Michigan’s Leelanau Peninsula.

This freshwater spring fills with 10,000 gallons of water per minute.

The only way to see Pittsburgh is from the top of this lookout point, just like the ancient members of the native peoples did.

This eerily well-preserved coal town was saved from destruction by a Sean Connery movie.

One of the steepest streets in the United States makes an intriguing challenge for cyclists.

The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

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

Mysterious rocks that ring musically when struck.

An abandoned railroad tunnel transformed into a creepy path for hikers and cyclists.

The last remnants of Fort Pitt also hold the distinction of being the oldest structure west of the Allegheny Mountains.

Where the oil industry began.

"Where the ducks walk on fish."

The Cold War-era "underground Pentagon" is a sprawling subterranean hideaway for the Defense Department.

This picturesque stream was up until recently the site of a ten story mountain of slag and sewage.

The only geyser in the state of Pennsylvania is caused by pressure from an abandoned coal mine outside of the ghost town Centralia.

Steepest flood safety railway in the entire world.

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