The industrial city of Cologne sits in the north western German state of Rhine-Westphalia, founded on both sides of the Rhine River. Cologne was founded by Romans in the 1st century AD and became one of Germany’s major harbours during medieval times. Rent a car from Cologne Airport, and visit the architectural and historical sights of the city. Visit the most iconic monument the Kölner Dom cathedral, the largest cathedral in Germany and climb its 509 steps. Enjoy panoramic views of the city from KoelnTriangle public visitor platform, while you can experience the history city’s art and architecture at the Roman-Germanic Museum.