Secret Swing.

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

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

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

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

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

The four tall pillars once marked the entrance of the historic Seattle church that fought for women's suffrage and civil rights.

42nd story Pyramid shaped penthouse tops Seattle's oldest skyscraper.

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

An old-timey peepshow allows visitors to gawk at some of the world's most freakishly large footwear.

The last masonry skyscraper ever built reveals a transitional moment in architectural history.

First planned industrial community in the United States.

For more than 50 years, an iconic sign has greeted visiting “fudgies” to the Traverse City area.

Chicago's Navy Pier on Lake Michigan was a training hub for aircraft carrier pilots during WWII.

Small and slightly hidden, the American Writers Museum is preserving the legacy of America's finest authors.

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

A spectacular remnant of an Adler and Sullivan masterpiece that was destroyed in 1972.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

This $3 million model train takes you through Chicago, Seattle, and the thousands of miles in between.

These chunky stone towers out in Lake Michigan are the key to Chicago’s drinking water.

The final resting place of the world's first nuclear reactor.

The world's largest collection of ship figureheads includes figures from legends and history alike, from Sir Lancelot to Abraham Lincoln.

On the grounds of this study, Lew Wallace composed "Ben-Hur: A Tale of the Christ" and many other works.

At the top of the hour, this steam-powered clock's eight brass whistles play "Back Home Again in Indiana."