Guided tour in the Cologne Cathedral and the Treasury The world-famous structure with its gigantic dimensions and rich furnishings has a breathtaking effect on its visitors even today. After the foundation stone was laid in 1248, it took more than 600 years until the Cathedral was finished in the 19th century. The many well-preserved stained-glass windows and the golden glow of the Shrine of the Three Kings determine the appearance of the interior first and foremost. Another attraction enriching the Cathedral since 2007 is the highly regarded and controversial window by Gerhard Richter. In the Treasury venerable relics, liturgical devices, vestments and insignia from the 4th to the 20th century are shown.