The St. Nikolai-Kirche, is the oldest church in Berlin, the capital of Germany. The church is located in the eastern part of central Berlin, the borough of Mitte. The area around the church, bounded by Spandauer Straße, Rathausstraße, the River Spree and Mühlendamm, is known as the Nikolaiviertel 'Nicholas quarter', and is an area of restored medieval buildings. The church was built between 1220 and 1230, and is thus, along with the Church of Our Lady at Alexanderplatz not far away, the oldest church in Berlin.

The Nikolaiviertel is an old quarter of the German capital of Berlin, founded c. 1200. Together with nearby Cölln, they jointly make up Alt-Berlin, the reconstructed historical heart of the city. Located in the Mitte locality, it is five minutes away from Alexanderplatz.