5. Cologne Cathedral – Cologne, Germany
The Cologne Cathedral, also known as Kölner Dom, is a magnificent Gothic masterpiece that dominates the skyline of Cologne. With its stunning architectural details, including intricate stone carvings and stained glass windows, the cathedral is a UNESCO World Heritage site and one of Germany’s most important cultural landmarks. Visitors can climb the 533 steps to the top of the south tower for panoramic views of the city and the Rhine River.