A lush indoor jungle fills this bustling Madrid transportation hub.

The largest Art Nouveau complex in the world is a Barcelona hospital with a 600-year-long history.

The world's largest wooden structure.

This semi-secret storybook hedge maze is also the oldest garden in the city.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

This stunning mass of ice spans 121 square miles and is still growing.

The inspiration for the Patagonia Clothing logo, Cerro Fitz Roy turns pink at sunrise.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

A strangely forgotten claimant to the much contested title of "Source of the Nile."

A desert that rolls right up to the ocean, where it's so dry animals live off the fog.

The king of U.S. high points towers over every other peak on the continent.

The ghostly remains of what was once the world's richest copper mine.

A serene space tucked amid the skyscrapers of Hong Kong's bustling financial district.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

Commonly acknowledged as the only public monument to the Devil himself.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

A stone slab in Madrid marks the point from which the distances of Spain's national roads are measured.

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

Rare karst landscape eroded from a flat seabed.

Spanning the El Chorro gorge, this pathway used to be one of the most dangerous crossings in the world.

This stoic, if derpy, giant stands as a monument to Oregon's statehood and the novelty culture of yesteryear.

This sandstone mansion was the home of two of Oregon's most important pioneers.

While it is not equipped to peer into outer space this observatory looks like it was built on the moon.