The Tannheimer Tal is a high valley, at an elevation of about 1,100 metres, in the Tannheim Mountains, which are part of the Allgäu Alps in the Austrian state of Tyrol.It is a left sided tributary to the lech river.
Wikipedia https://en.wikipedia.org/wiki/Tannheimer_Tal
Coordinates 47°29'16.112" N 10°33'36.8" E