Forget your boot camps. This is the old Dutch day of dealing with thugs. Opened in 1596 as a house of correction, the Rasphuis (Grating House) was one of several such institutions around the old city. Here men were put to work grating Brazilian hardwood for use in dye and paint. All that remains now is the 17th century gateway, showing a wood laden cart being pulled by wild animals...an allegorical refence to taming anti-social elements in society! The Rasphuis's female equivalent, the Spin Huis (Spinning house), stood on the Oude Zijdes Achterburgwal.