Ketzin (German: [kɛˈt͡siːn] ^ⓘ, official name: Ketzin/Havel) is a town in the Havelland district, in Brandenburg, Germany. It is situated on the river Havel, 17 km northwest of Potsdam, and 40 km west of Berlin.

Ketzin was first mentioned in 1197 by a document. Until 1571, though, Ketzin was kept in the Bishopric of Brandenburg, the imperial principality of the Prince-bishop of the Diocese of Brandenburg and according to the law, not part of the Margraviate of Brandenburg.^[3]

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  Development of Population since 1875 within the Current Boundaries (Blue Line: Population; Dotted Line: Comparison to Population Development of Brandenburg state; Grey Background: Time of Nazi rule; Red Background: Time of Communist rule)
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  Recent Population Development and Projections (Population Development before Census 2011 (blue line); Recent Population Development according to the Census in Germany in 2011 (blue bordered line); Official projections for 2005-2030 (yellow line); for 2017-2030 (scarlet line); for 2020-2030 (green line)

The town counts 6 Ortsteile (civil parishes): Etzin, Falkenrehde, Knoblauch, Paretz, Tremmen and Zachow.

The Ketzin Cable Ferry, a vehicular cable ferry, crosses the Havel between Ketzin and Schmergow.

Media related to Ketzin/Havel at Wikimedia Commons