The Reintal ("Rein Valley") is the name given to the upper and lower valleys of the River Partnach between the Zugspitzplatt plateau and the Partnachklamm gorge. A hiking route to Germany's highest mountain, the Zugspitze runs through the valley.
The valley was formed during the Würm Ice Age by the Reintal Glacier and then deepened by the Partnach in the post-ice age period after the retreat of the glacier to the periphery of the Schneefernerkopf mountain. The upper Reintal, which was shaped by the glacier and today forms a U-shaped glacial valley, ends between the Hohe Gaifkopf in the west and the Schachen in the east. The lower Reintal lies in the area of the former glacial lake of the Loisach Glacier, into which the Reintal Glacier flowed from the southwest. It is a V-shaped valley and has been predominantly shaped by the Partnach river.
Together with the Höllental valley to the north, the Reintal divides the Wetterstein Mountains into several ridges. The northern periphery is formed by the arêtes of the Höllentalspitzen (2,743 m) and the Hohe Gaifkopf (1,864 m). The highest points on the southern flank of the valley lie on the Hochwanner (2,744 m), the Hinterreintalschrofen (2,670 m) and the Dreitorspitze (2,682 m). The valley floor lies at elevations between 1400 m above NN at the source of the Partnach river, 1,002 m at the entrance to the gorge of the Hinteren Klamm and 797 m at the start of the Partnachklamm gorge, in the upper Reintal therefore about 1300 to 850 m above the surrounding mountain peaks. [?] In the upper Reintal the rubble from rockslides from the southern faces of the Hochwanner and Hinterreintalschrofen also play a rôle in the shaping of the valley. These have spilled into the old glacial valley, forced back the course of the Partnach to the north and, in places, impounding it.