The small watermill built on Liiva spring on Möldri farm in Kahala village, Kuusalu parish, was used to grind straight flour, wholemeal flour as well as rye coarse meal for making gruel during the spring and autumn floods; it would also make groats. Kahala mill was one of four watermills of Kolga manor. The mill was brought to the museum in 1962 and opened for visitors in 1969.

It is believed that water mills used to grind flour on our springs and rivers earlier than windmills in windy locations: the Estonian word for ‘mill’ comes from the combination of ‘water’ and ‘stone’. They have apparently been known since the beginning of the 13th century, which is when written records about such buildings appeared. In the 19th century, major rivers of the continental part of Estonia had entire cascades of watermills where people ground flour, sawed timber to make boards, carded and spun wool and did smith work.

Kahala mill has an undershot water wheel, which means that it is set in motion by water running under it. In its turn, the water wheel moves the millstones by means of a pinion drive. The ground floor of the mill built from broken limestone is where the ‘water room’ with the water wheel and the ‘mill hall’ with the grinding mechanism are located; slightly above the latter, there is a floor with millstones made of granite. Upstairs there is the ‘sack floor’ built of logs over the mill hall. The amount of the water flowing on the wheel through the sluice is adjusted by means of a water gate set in motion with the lever on the floor above the water room.

Generally, red granite with black bits that look like coal was the preferable material for millstones. The bottom millstone had to be harder than the top one, because two hard stones were believed ‘not to grind good flour’. ‘Flour grooves’ were cut on the millstone running from the centre to its edges, and they had to be refreshed regularly.

The earliest known miller of Kahala mill was Villem Leimann, a waiting-man from Kolga manor. In the middle of the 19th century he married Eltse, a manor maid, and for his good services the baron gave him Möldri farm with the mill to live on free of charge. Later the couple’s son Kustas took the trade over. After his death, his daughter Maali, who was educated in town, inherited the place and lived there with her husband, a former bank clerk. Maali’s son could not cope with running the mill, and it was sold. The new owners ‘upgraded’ it to the extent that they could. The museum displays the restored watermill as it was in Villem’s time.