The Platten manmade ditch is an outstanding example of the technical capabilities of the water engineers of the 16th century. It is the longest water supply course for mining in the Czech part of the Erzgebirge and is still functional today. Built between 1540 and 1544 and with a length of 13 kilometres, the ditch provided motive water for dozens of mines and ore dressing works from Boží Dar to Horní Blatná right into the 19th century. The ditch is up to two metres wide and up to one metre deep. The bed of the ditch was reinforced using wooden planking. Following maintenance carried out between 1995 and 2001, the ditch features (among other things) ten relief overflows, 25 jetties and culverts, and 39 sand and gravel traps.