Berlin Brandenburg Airport is in zone C. The tickets are sold in zone pairings, such as AB, BC and ABC. The U-Bahn runs from 4 a.m. until 1 a.m. during the week and 24 hours on the weekends.

Berlin is one of the largest cities in Europe (about nine times the size of Paris), so traversing this gigantic metropolis in a limited period of time can seem daunting. Attractions are spread out ...