 The buildings are made of painted wood on a brick foundation , with tiled roofs , and an extruding hatch covering the main entrance of the higher building . The gristmill , originally used to grind spelt , later ground bread wheat , and then a sawmill was added . It has a water wheel of 9 @.@ 30 metres ( 30 ft 6 in ) in diameter , consisting of 44 paddles of 80 centimetres ( 2 ft 7 in ) width , which makes it the largest water wheel in the Netherlands . The gristmill is still in functioning order , and uses a pair of Cullen millstones from Mayen ( " Cullen " for " Cologne " , where such millstones were marketed from ) , and a pair of cast millstones , both 17 hands in diameter or 1 @.@ 50 metres ( 4 ft 11 in ) . Only some remainders are left of the sawmill , including one of only two watermill circular saws in the Netherlands . Inside the larger mill is a room for the assistants of the miller , where the names of millers and their assistants have been carved in the wood . 
