Secret Swing.

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

The Incredible Hulk, Yoda, Mulder and Scully, and many many others watch over the mean streets of Toronto.

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.

Hidden inside one of the world's most well-visited zoos is a secret plaque promising eternal life.

Every year model trains zip through a miniature New York City that's now 150 landmarks strong.

The first and only carousel with a lineup entirely of insects.

Piano-making empire filled with 200-year-old steam machines still churning out 1,000 instruments a year.

An ancient knight and a symbol of the city's freedom.

A full figure 4th century incorruptible saint lies in a glass coffin in Croatia.

A wunderkammer of gold and silver reliquaries and ancient saintly bones.

Gargoyle head that brings good luck.

This deconsecrated church has seen many uses, from a tobacco storehouse to a cinema.

Two stone columns flank the grand Venice square, but there were supposed to be three.

This strange bovine gargoyle is said to have been put in as a passive aggressive form of revenge.

Renaissance hospital featuring a rotating door into which unwanted babies were dropped.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

The middle finger of modernity.

Museum celebrating the ocean, with the largest wunderkammer dedicated to sea exploration.

Found art has transformed this Pittsburgh neighborhood into a psychedelic dream.

An unusual assortment of steerable wooden sleds is on display in a library in New Jersey where they were first invented.

On the Hudson resides one of the largest clocks in the world.

Historic town settled in the 19th century because of its convenient location along a popular coal transport route.