The final reach of the Spree is where it is best known. It flows through the city centre of Berlin to join the River Havel in Spandau, one of Berlin's western boroughs, which itself ultimately merges with the Elbe to enter the sea in Cuxhaven, after flowing through Hamburg. On its route through Berlin, the river passes Berlin Cathedral ("Berliner Dom"), the Reichstag and the Schloss Charlottenburg. The renowned Museum Island ("Museumsinsel"), with its collection of five major museums, is an island in the Spree.