The Zirler Berg is on the southeastern extremity of the Seefeld Plateau, which is roughly 1,200 m above sea level and lies between the Wetterstein (north), Karwendel (east) and Mieminger Ranges (west) and drops away to the Inn valley to the south and 600 metres below.

The actual summit of the Zirler Berg and its southern flank facing the Inn valley consists of strata of main dolomite; in the area of the mountain top, however, there are morainic deposits.

[3][4] Due to the steep gradient there are several escape lanes between Leithen and Zirl that branch off the downhill carriageway; they runn slightly uphill so that in an emergency, vehicles, especially lorries, can be braked by the gravel roadbed.

The gradient also means that bicycles are not permitted on the downhill carriageway; although they are allowed to climb the road, this is not recommended due to the high levels of traffic.

East of the mountain the railway enters a wide curve over bridges and through tunnels on the south flank of the Rauenkopf and southwestern side of the Brunstkopf, crossing the Schlossbach.