These curious caverns have been home to mushrooms, gangsters, and disco.

The last four extravagant street signs of London's historic banking street.

A little-known cafe in an old copper bridge tower with 360-degree views of the harbor.

The oldest amusement park in the world has been providing a nice spot to have some fun since the 1500s.

Nearly 40 miles and 1,000 years of limestone mines under Denmark.

Beneath Denmark's Højbro bridge, a bronze merman and his seven sons forever mourn for the mother and wife who left them for land.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

Opulence and fantasy collide in this royal chair which is supposedly made with unicorn horns.

This sublime architectural marvel is a rare example of an expressionist church.

A natural wonder in south Denmark.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.

This colorful artistic feature atop a Danish art gallery allows visitors to stroll through a rainbow.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Copenhagen's celebrated theme park and gardens.

Julia Morgan's Moorish-Gothic labyrinth of fountains, trees, natural light and Oakland's notable dead.

Worker-owned cooperative and resource for those looking to lighten their ecological footprint.

The oldest lawn bowling club in the United States.

The Flatiron Building's storied West Coast cousin is a lot more into religion.

The century-old bell and clock tower at UC Berkeley is the third-tallest in the world, and has fossils.

Once the largest winery in the world, this castle-like building now sits abandoned on the San Pablo/San Francisco Bay shore.

Odd stone and concrete monuments in the "Poet of the Sierras" eclectic folly garden.

This whimsical seashell-shaped place of worship was designed to blend into its surroundings.

Once the largest windmill outside of Holland, with enormous 114 foot sails.

A massive ultra-modern church presents a science-fiction view of Catholicism's inclusive future.