Upper Harz Ditches

The Upper Harz Ditches (German: Oberharzer Gräben, pronounced [ˌoːbɐhaːɐ̯tsɐ ˈɡʁɛːbm̩]) are hillside ditches, running roughly parallel to the contour lines, that were laid out in the Upper Harz in Germany from the 16th to the 19th centuries to supply water power to the silver mines there.

The embankments are frequently protected from erosion by a dry stone wall.

In most cases, they also act as inspection paths for the ditch keepers (Grabenwärter) and, today, as public footpaths.

As protection against seepage the embankment and bed of the ditch are usually sealed with grass sods or clay.

When water levels are high these have to be opened, i.e. the boards controlling the flow must be removed.