Twisted buildings adorn the banks of the Rhine river.

The last bastion of Roman presence north of the Alps looms over a German town.

The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

A ruined castle stands atop a hill surrounded by dragon lore.

Thousands of flowers create enchanting pink tunnels over the city streets.