Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

This line of 12 tower mills described in the story of Don Quixote is among the most iconic landscapes in Spain.

A medieval village holds a very modern hotel.

The world's largest wooden structure.

These magnificent city walls rise from the barren sun-baked Spanish plains like something straight out of a fairytale.

A lush indoor jungle fills this bustling Madrid transportation hub.

An ancient Egyptian temple in the middle of Madrid, Spain.

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

A magnificent, reportedly haunted mansion built for a composer by Spiritualists.

One of the largest trees of its kind in California.

The world's largest outdoor organ is played weekly by one of just two civic organists in the U.S.

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

This historic graveyard was partially paved over to create a streetcar line.

The most unique castle in all of Southern California, entirely constructed from repurposed materials.

A restored 1920s cascade stairway provides one of the best views of Oakland's Lake Merritt.

A massive sustainable farm designed by the mastermind behind Central Park.

This 38-drawer structure claims the superlative title, but it isn't the world's only giant filing cabinet.

A man-made island in scenic San Francisco Bay.

This Pringle-shaped ledge makes for the perfect photo op.

A playground built by the kids that is a child's wonderland, and a helicopter parent's nightmare.

The hidden jewel of Disneyland: a members only playground for the Disney elite.

Named after a bandit and the star of several Hollywood prehistoric landscapes, these sandstone formations are a historical part of the Los Angeles natural landscape.