Untergiesing-Harlaching (Central Bavarian: Untagiasing-Harlaching) is the 18th borough of Munich, Germany, mostly the districts of Untergiesing and Harlaching. The borough's western border is the river Isar, in the south it borders on Grünwald and the Perlacher Forst [German-language Wiki: Perlacher Forst] (Perlach Forest), to the north-west on the Munich borough of Obergiesing and to the north on the borough of Au-Haidhausen.