Potsdamer Platz (German: [ˈpɔtsdamɐ plats] (listen), Potsdam Square) is an important public square and traffic intersection in the center of Berlin, Germany, lying about 1 km (1,100 yd) south of the Brandenburg Gate and the Reichstag (German Parliament Building), and close to the southeast corner of the Tiergarten park. It is named after the city of Potsdam, some 25 km (16 mi) to the south west, and marks the point where the old road from Potsdam passed through the city wall of Berlin at the Potsdam Gate. After developing within the space of little over a century from an intersection of rural thoroughfares into the most bustling traffic intersection in Europe, it was totally destroyed during World War II and then left desolate during the Cold War era when the Berlin Wall bisected its former location. Since German reunification, Potsdamer Platz has been the site of major redevelopment projects.

The history of Potsdamer Platz can be traced to 29 October 1685, when the Tolerance Edict of Potsdam was signed, whereby Frederick William, Elector of Brandenburg-Prussia from 1640-1688, allowed large numbers of religious refugees, including Jews from Austria and Huguenots expelled from France, to settle on his territory to repopulate it following the Thirty Years' War (1618–48). Several new districts were founded around the city's perimeter, just outside the old fortifications. The largest of these was Friedrichstadt, just south west of the historic core of Berlin, begun in 1688 and named after the new elector, Frederick William III, who became King Frederick I of Prussia. Its street layout followed the Baroque-style grid pattern much favoured at the time, and was based on two main axes: Friedrichstraße running north–south, and Leipziger Strasse running east–west. All the new suburbs were absorbed into Berlin around 1709–10. In 1721-3 a south-westwards expansion of Friedrichstadt was planned under the orders of King Frederick William I, and this was completed in 1732-4 by architect Philipp Gerlach (1679–1748). In this expansion, a new north–south axis emerged: Wilhelmstrasse.