Botjes Zandgat is a sand quarry in Groningen with sometimes very good visibility, but little life. Visibility values up to more than 18 meters are not uncommon in times when there is nog dredging going on. Diving is unfortunately forbidden, although illegal diving has been going on for years. In 2011, the southwest corner of this excavation was set up for daytime recreation. Officially this area is called Botjes Zwembaai. Botjes Zandgat is named after Feiko Botjes, who had a farm at this location at the end of the nineteenth century.