Denkendorfer Erlachsee, Natural reserve in Denkendorf, Germany.

Denkendorfer Erlachsee lies on the L 1204 between Denkendorf and Neuhausen auf den Fildern, one of the few standing waters on the dry Filder plain. The monks of Denkendorf monastery dammed a wet hollow here; a spring about fifty metres south feeds it, and the Erlachgraben drains it eastward through the former monastery grounds to the Körsch. Reed beds, silted margins and alder carr fill the basin.

The pond was created in 1129 by monks of Denkendorf Monastery, who dammed an existing wet hollow to raise carp for the fasting period. The outflow runs through the Erlachgraben eastwards, through the former monastery grounds, to the Körsch. On 18 October 1937 the area was designated a protected landscape component, and on 15 December 1975 a 15.5-hectare landscape protection area named "Erlachsee" followed.

Local residents of Denkendorf call this water body simply 'Dor Sae' in their dialect, as it remains the only lake in the immediate region. The name reflects how important this place is as a landmark in everyday local life.

A footpath runs along part of the lake; the other part is fenced off and entry is forbidden. The reserve lies on the L 1204 between Denkendorf and Neuhausen auf den Fildern. The ground near the shore is wet, so wear sturdy shoes.

The lake lies on the L 1204 between Denkendorf and Neuhausen auf den Fildern, one of the few standing waters on the dry Filder plain. Because no other lake exists nearby, old Denkendorf residents simply call it "Dor Sae" ("the lake"). Its outflow runs through the Erlachgraben eastward, through the former monastery grounds, to the Körsch.