This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

This forgotten Frank Lloyd Wright house is an architectural marvel at the end of a sleepy residential street.

Once strictly off-limits, this lower level housing curious and priceless vehicles of the Petersen Automotive Museum is now open to the public.

Most famous work of one of Frank Lloyd Wright's sons.

This weird abode has inspired everything from the "House On Haunted Hil" to a robot hunter's pad.

A museum in the former home of Marxist revolutionary Leon Trotsky.

The famous artist couple lived and worked here, in two different houses separated by a bridge.

Frida Kahlo's childhood home, now a museum of her life and works.

Catalonia Tradition: Beating the hollow Christmas log until it defecates in your fireplace.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

Bask in the 19th century grandeur of an eccentric Freemason millionaire's private gardens.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

A giant Troll lurks under one of Seattle's oldest bridges.

James Turrell's total color immersion art installation, hidden on the top floor of a luxury handbag shop.

Try not to get slimed in Tribeca.

A long-vacant Scottish Rite temple in Hollywood has been converted into an art museum filled with Masonic relics.

Hidden in one of the skyscrapers on Bunker Hill, this museum features an 1895 stagecoach and peers into California’s gold-lined history.

This quirky UFO-shaped curiosity is often mistaken for the airport’s control tower.

The blinking light atop the iconic landmark has been sending secret messages for decades.

The space-age building is home to one of the few remaining rotating restaurants in America, and the only one that inspired a 1980s sitcom.