You are standing before one of the most iconic landmarks in the world. Dominating the skyline of Cologne, this Gothic masterpiece reaches a height of one hundred fifty-seven meters, featuring twin spires that were, for a brief window between eighteen eighty and eighteen eighty-four, the tallest structures on earth. As you look up at the intricate stone lace of the facade, you are seeing what locals call their kilometer zero, the emotional heart of the city that serves as a beacon of home for anyone returning to Cologne. This site has been occupied by Christian churches since about the fourth century, but the structure you see today is a testament to nearly seven hundred years of human ambition. Take a moment to orient yourself on the vast pedestrian plateau known as the Domplatte before we head inside to uncover the secrets held within these blackened stone walls.