The largest underground pedestrian tunnel system in the U.S. mostly caters to the people working in the offices above, but provides a great, air-conditioned way to traverse the city.

The mountaintop inspiration for Umberto Eco's "The Name of the Rose."

A marvel of Byzantine engineering under the streets of Istanbul.

Once an opulent Art Nouveau hotspot, the Constanța Casino is one of Romania's most beautiful abandoned buildings.

The peaceful space is adorned by paintings by the famed abstract artist Mark Rothko.

This tiny, hurricane-resistant house in Galveston is one of the city's most notable architectural oddities.

At the "Garage Mahal" in Houston, car culture is about more than just driving.

One man's homage to the orange as realized through a long-term folk art labor of love.

In Houston's airport, a cow is properly equipped to jump over the moon.