The Singelgracht
The Singelgracht surrounds the centre of Amsterdam. After the construction of the Grachtengordel (canal belt/zone) in the 17th century the Singelgracht formed the outermost boundary of the city. The grachtengordel was close to the city ramparts, which formed the defence line.
Within these ramparts a stronghold was build on which windmills were placed. At the inside of the ramparts lay the Lijnbaansgracht, named after the lijnbanen which were alongside of the ramparts, parallel to the Singelgracht.
For two centuries Amsterdam had a characteristic crescent shaped ground plan. In the last quarter of the 19th century Amsterdam extended beyond the Singelgracht and the ramparts were levelled. Nowadays the Marnixstraat, Weteringschans and Sarphatistraat are situated over here.
On the outside of the Singelgracht the Nassaukade, Stadhouderskade and Mauritskade were created. A part of the stronghold was levelled and the canal was straightened. At some places you still can recognize the old sinuous shape.
Only one windmill of the stronghold remained: Windmill the Gooyer.
Don't mix up the Singelgracht with the Singel!!!