Berlin Metro

The waiting travelers huddle inside their down coats, glancing at each other, occasionally checking in with their strange neighbor, getting a friendly nod that confirms the chill and labor of the morning's commute. You watch for the train, hoping it arrives soon so that you can get on to your office desk and the loving little heater that sits below it. The Berlin U-Bahn is a rapid transit railway in Berlin, the capital city of Germany, and is a major part of the public transport system of that city. Opened in 1902, the U-Bahn serves 173 stations spread across ten lines, with a total track length of 146.3 kilometres (90.9 mi), about 80% of which is underground. Trains run every two to five minutes during peak hours, every five minutes for the rest of the day and every ten minutes in the evening. They travel 132 km (83 mi)[clarification needed], carrying 496 million passengers, over the year. Designed to alleviate traffic flowing into and out of central Berlin, the U-Bahn rapidly expanded until the city was divided into East and West Berlin at the end of World War II. Although the system initially remained open to residents of both sides, the construction of the Berlin Wall and the subsequent restrictions imposed by the East German government limited travel across the border. The system was reopened completely following the fall of the Berlin Wall, and German reunification.