This abandoned factory on the Hudson River once churned out a million bricks a week.

This stone tower marks a lookout point over the historic Washington Crossing, and maybe some buried treasure.

In which a local geological marvel becomes a quaint roadside attraction.

A winding, cliffside stretch of road overlooking the Delaware River.

A walk through the historic city center, under the streets of Seattle.

One of the oldest of its kind.

This Delaware River bridge is emblazoned with a catty slogan from a more prosperous time.

Elaborate drama imparts an appreciation for 19th century hardships.

This blowhole is supposedly caused by a trapped monster.

These ancient sacred grounds granted amnesty to those who managed to reach them.

These picturesque Hawaiian falls are home to a rare species of fish that uses a special sucker to climb up cliffs.

A sealed test tube said to hold Thomas Edison's dying breath was given to the inventor's friend and mentee, Henry Ford.

The body of St. John Neumann and his collection of hundreds of relics, on display in a Philly church.

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

Dedicated to the art and science of glass in equal measure, this space is as much laboratory as museum.

The wooden octagon in which Huckleberry Finn and A Connecticut Yankee were born can still be visited in upstate New York.

The Hudson River School comes alive at this palatial estate.

Holy Hindu shrine in an enormous, monkey-filled limestone cavern.

Breathtaking and huge 430 year old maps of Italy.

The largest tea plantation in Southeast Asia supplies gorgeous vistas alongside tea for the surrounding countries.

This trio of Australian rock spires may have inspired aboriginal legend or just modern tourism.

Yale University's home for rare works, including the mysterious Voynich Manuscript.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.