The Elmertsbach, also Häggraben or Schlingengraben is a right tributary (3.5 km long) of the Haggraben in the district of Aschaffenburg in the Bavarian Spessart.
The Elmertsbach has its source in an old well, in the forest west of Rückersbach at the pile hole. It runs as a border stream between the districts of Hörstein and Rückersbach as well as Hörstein and Dettingen am Main on the edge of the vineyards in a westerly direction. It emerges from the forest and feeds a small pond southwest of Hörstein. The vanished village of Bruchhausen is believed to be near this point. In summer the Elmertsbach has little water, so that the small pond has no outflow. The Elmertsbach flows into the Haggraben near the federal highway 45.
The Elmertsbach is also called Häggraben. Due to the similarity in name to its receiving water, the Haggraben, an earlier recognition as an upper course can be assumed. The Elmertsbach was at times a tributary of the Main, which once flowed in this ancient Main valley. The valley in the upper reaches of the stream can be seen as the southern boundary of the Hahnenkamm mountain range.
The Elmertsbach was not always just a border stream for the districts. It used to separate the areas of two historical states in the Confederation of the Rhine. On the right side was the territory of the Grand Duchy of Hesse, to which Hörstein in the Alzenau district in the Starkenburg province belonged. On the left was the Grand Duchy of Frankfurt with the villages of Rückersbach and Dettingen in the department of Aschaffenburg. There is also a series of historic boundary stones from 1810 on this boundary line along the course of the stream, some of which no longer exist today.