This European Capital's 4 main city center canals are Prinsengracht, Herengracht, Keizersgracht & Singel
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Six major concentric canals ring the Old Centre; the Singel, the Herengracht, the 
Keizersgracht, the Prinsengracht, the Lijnbaansgracht, and the Singelgracht,... [DOC] [TLE] Tourist attractions in Amsterdam [PAR] The main Amsterdam tourism attractions are museums.