Klara Sjö (Swedish for "Lake Klara") is a canal in central Stockholm, Sweden.Separating the island Kungsholmen from the northern city district Norrmalm, the canal connects Barnhusviken to Riddarfjärden. Together with Barnhusviken, Karlbergssjön, and Karlbergskanalen, it thus forms part of the nameless body of water which separates Kungsholmen from the mainland districts north and east of it, Norrmalm and Vasastaden.