Despite violent work crews and massive delays this abandoned canal tunnel was built to last into the modern day.

Pennsylvania's largest cave in Laurel Highlands becomes its first underground state park.

The penultimate and final resting places of British General Edward Braddock—minus a few bits and pieces.

The house that Frank Lloyd Wright "(shook) out of his sleeve at will" at the age of 86.

Chase waterfalls, hiking trails and more.

Frank Lloyd Wright’s most iconic home dangles over a Pennsylvania waterfall.

The last holdout of a pre-Civil War rebel who took the matter of slavery into his own hands.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

The highway's southernmost spot is a beloved local attraction.

The museum chronicling a treasure hunter's dream, fulfilled.

This 140-year-old beacon off the Florida Keys marks the wreck of a Navy ship that once roamed the Caribbean hunting pirates.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Country fans may flock to Nashville's music scene, but this Appalachian town is where the genre was born.

One street divides a single town that stands in two U.S. states.

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

There aren't too many operational funiculars around, but Pittsburgh has two!

America's post-nuclear-attack chambers of Congress.

The oldest arched-covered bridge in Virginia has truly withstood the test of time.

The location where the American Revolution ended.

Colorful curls of hand-blown glass form a captivating tower in San Antonio's Central Library.

These unusual rooms on wheels are holdovers from the 1960s.

Florida might be at its most surreal in this museum devoted to the famed Spanish artist.

Climbing this abandoned railway leads to breathtaking vistas of O‘ahu.

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