This elegant arc of a waterfall marks a religious turning point.

The most powerful waterfall in all of Europe.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Rising from the sea like a stone monster.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

The world's largest wooden structure.

The final resting place of the great navigator, or maybe his brother.

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

Holy Grotto of Montserrat Monastery holds one of Europe's mysterious black Madonnas.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

Spain's stunning solar energy plant.

This cemetery features modernist statues as strange as its name.

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.

A raised boardwalk winds through a thicket of stunted, century-old trees no more than nine feet tall.

A trash dump made beautiful by nature's power.

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

Canyon walls shrouded in ferns.