Low-frequency noise compared to an idling train can only be heard by some of this industrial town's residents.

A statue commemorating a beloved stray dog who was adopted by the entire neighborhood where he lived.

A reproduction of the famous prehistoric cave paintings is hidden underground at the National Archaeological Museum.

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.

A somewhat mysterious biomedical museum housed inside a Spanish university.

A living art gallery painted on a canvas of Monterey pine trees.

A landscape decorated with enormous skull sculptures.

This subterranean spot might be the epitome of Japan's baroque, retro coffee houses.

A Stockholm metro station is home to an escalator that is not only the longest in Sweden, but among the longest in the world.

The only diamond mine in the world where you can keep what you find.

Dozens of large, brightly-colored paintings adorn the walls of the "street art capital of Iceland."

This remarkable prehistoric town is full of watchtowers and houses that have withstood thousands of years.

Experience park where visitors are told to expect the unexpected.

The wooden house where the jazz great learned to play the piano.

Enormous ants wielding giant pine needles guard a Stockholm real estate company's office.

A magnificent place to see authentic paleolithic cave paintings that are an astounding 33,000 years old.

These docile dragons are ideal inhabitants for the conservatory greenhouses.

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

This Manhattan museum houses one of the largest collections of Spanish art and manuscripts outside of Spain.

Unusual books about food and drink abound in this 19th-century New York townhouse.

The first piece of public art dedicated to LGBT rights.

This translucent sculpture represents a quintessential component of New York City's skyline.

Rat sculptures try to infiltrate the Graybar Building in an architectural tribute to New York City's nautical history.

Beautiful mosaics cover the first stations opened on New York City's newest subway line.