An outsider art duo's yard has been turned into a whimsical public gallery.

Spanning an elevation of 160 feet and containing 388 steps, this is Seattle's longest staircase.

An enclosed rotunda at the Henry Art Gallery in which viewers can look up and see the uninterrupted sky.

"The House That Love Built" is shying away from "The House That Ghosts Love."

A whimsical village of unique treehouses resides in a Washington forest.

This semi-secret garden in south Seattle emulates a traditional Japanese garden using the plants of the Pacific Northwest.

Spain's largest bullring offers a unique glimpse at architecture and history.

A small house in Tazones, completely covered in shells.

The quirky - and private - constructions of a secluded artist depict the house of God.

This ancient rock painting is the oldest evidence of humans’ love affair with honey.

A magnificent, long-abandoned castle built in the wake of the reconquest of Spain.

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

A cheese discovery made by shepherds became the pride of a region.

This postmodern apartment block was designed to be a vertical neighborhood.

A five-square-mile slice of Spain on the Mediterranean coast of North Africa.

This magnificent castle grew from a small Moorish fortress, and reportedly inspired two iconic Disney castles.

A whimsical garden of outsider art in the Spanish countryside.

For one day every month Barcelona's Estació de França transforms into a market for model trains.

This ancient Spanish castle sits high upon a hilltop.

Its appearance in "Game of Thrones" may spur on the long-awaited restoration of this medieval shipyard.

Rare karst landscape eroded from a flat seabed.

This quaint Spanish village agreed to be painted blue as a marketing stunt but found that they preferred it that way.

Earth's rocky history has rarely glittered so brightly as it does in this Spanish museum.

A Romanesque tower appears when water levels drop.