While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

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

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

Before Nixon, "watergate" meant canals.

Washington's iconic carousel has a nice piece of Civil Rights history.

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

A clone of a cloned tree that was so important it allegedly had its own guards.

The most accurate timepiece in the world.

Decades before the scandal, this staircase on the river was a literal "water gate."

A fantastic place to see murals, and an important location in the history of Toronto's legal street art scene.

This massive, ancient stone was disassembled and then put back together again.

One of the largest underground systems runs under Canada's largest urban center.

A collection of more than 12,000 shoes, displayed in a building shaped like a shoebox.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

This colorful creation wasn't always a welcome part of Toronto's Moccasin Trail Park.

One of Canada's most incredible rare book collections holds hundreds of thousands of gorgeous tomes that the general public can touch.

A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

A book collector's dream, this Toronto bookstore has the world's first "Biblio-Mat," a random book vending machine.

The oldest continuously operating fish market in the United States.

The national park was once a plantation estate.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

Home to items never before seen by the public.