In a month's time, it's all or nothing for you. You have exams at the University of Cologne. You have to present what is sacred to the people of Cologne. 

Before the big trembling begins, there is only one chance. Make a pilgrimage through the city from station to station. Solve all the puzzles and discover unique objects, works and brands without which Cologne would be unthinkable. You could also say: all this is sacred to the people of Cologne!

If you now also find out why all this is sacred to the people of Cologne, then your presentation will be a hit. Your exam is secured.