Unter den Linden ("under the linden trees") is a boulevard in the central Mitte district of Berlin, the capital of Germany. Running from the City Palace to Brandenburg Gate, it is named after the lime trees that line the grassed pedestrian mall on the median and the two broad carriageways. The avenue links numerous Berlin sights and landmarks.
Unter den Linden runs east–west from the site of the Stadtschloss royal palace at the Lustgarten park, where the demolished Palace of the Republic once stood, to Pariser Platz and Brandenburg Gate. Eastward the boulevard crosses the Spree river at Berlin Cathedral and continues as Karl-Liebknecht-Straße. The western continuation behind Brandenburg Gate is Straße des 17. Juni. Major north–south streets crossing Unter den Linden are Friedrichstraße and Wilhelmstrasse.
Unter den Linden, which sits at the heart of the historic section of Berlin, developed from a bridle path laid out by Elector John George of Brandenburg in the 16th century to reach his hunting grounds in the Tiergarten. It was replaced by a boulevard of linden trees planted in 1647, extending from the city palace to the gates of the city, by order of the "Great Elector" Frederick William. While the western part of the boulevard retained its character, the area around present-day Bebelplatz was integrated into the fortification of Berlin in the aftermath of the Thirty Years' War, visible until today as there are no trees.