Home to items never before seen by the public.

The industrial architecture honors the laborers who brought the Exposition Universelle of 1900 to life.

Once decrepit and slated for demolition, now one of the longest pedestrian bridges in the world.

This funicular railway rumbles along for a mile up the nearly vertical face of Chattanooga’s Lookout Mountain.

This replica of the Greek structure is in the heart of Nashville.

For decades, this waterfall remained hidden because of an artificial dam.

An unusual, super-sized grocery adventure awaits in an Ohio suburb.

Rare recess caves fill this unbelievably beautiful Ohio park.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

The final resting place to 300 Victorian-era pets hides inside the city park.

A church filled with the bones of hundreds of virgins martyrs—or so they say.

This museum housed in a former brothel explores the past and present of sex work in Amsterdam.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

Displaced highlanders would take shelter from the wet Scottish climate under the large walled bridge at Glasgow Central Station.

One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

A rare memorial paying homage to an altruistic woman from the 19th-century.

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

The final resting place of soldiers' loyal canine companions.

This historic pub has maintained much of its 1906 decor, including a small sequestered room for women, where orders were slipped through a tiny window.

A free public golf course hides in plain sight in the heart of Scotland’s capital.