This Scottish burial tomb once held hundreds of ancient eagle bones.

This tin chapel was built by POW's during World War II and is painted to look like something much more grand.

The true age of this ancient stone circle is unknown, but its stunning vista isn't in question.

Possibly the oldest of Britain's ancient henges is also one of its most stark.

Thanks to both terrific preservation and historic vandalism this ancient site is known as the "Heart of Neolithic Orkney."

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

A discreet little stairway on St. Nicholas Avenue leads to a quaint and unexpected cobblestone street of 19th century wooden rowhouses.

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

A student driver's nightmare.

The glowing blue Nymphaeum of Emperor Tiberius.

Breathtaking and huge 430 year old maps of Italy.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

The sister plane of the C-123 shot down during the Iran-Contra Affair has found a new purpose in retirement.

Four cars from the old system were once on display, but were removed in 2014.

Once a popular watering hole among longshoremen and shipyard workers, this neighborhood treasure spans more than 100 years of Red Hook history.

A big shiny gin and whiskey distillery in Sunset Park.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

The world’s first penitentiary, meant to be humane, drove men insane.

A layered tribute to the work of mosaicist Isaiah Zagar.

A unique sculpture park that specializes in the huge and bizarre.

Rivers of cattle blood gone, a strange Escheresque building remains, the last of its kind.

Impossibly life-like natural history models created out of glass by a father and son.

Two thousand artifacts from around the world collected by one woman who loved to travel.