U2 is a line of the Berlin U-Bahn. The U2 line starts at Pankow S-Bahn station, runs through the eastern city centre (Alexanderplatz) to Potsdamer Platz, the western city centre (Wittenbergplatz, Zoologischer Garten, Theodor-Heuss Platz) and finally to the Ruhleben terminal station. The U2 has 29 stations and a length of 20.7 kilometers (12.9 mi). Together with the U1, U3, and U4 lines, it was part of the early Berlin U-Bahn network built before 1914. The line between Potsdamer Platz and Zoologischer Garten was the western section of the "stem line" (Stammstrecke), Berlin's first U-Bahn line opened in 1902. From Wikipedia
