Singel

The Singel is one of the canals of Amsterdam. The Singel encircled Amsterdam in the Middle Ages, serving as a moat around the city until 1585, when Amsterdam expanded beyond the Singel. The canal runs from the IJ bay, near the Central Station, to the Muntplein square, where it meets the Amstel river. It is now the inner-most canal in Amsterdam's semicircular ring of canals. (Wikipedia)