Those who follow a small sign uphill at this natural bottleneck created by the two mountain ranges Wetterstein in the West (our viewpoint) and Karwendel in the East will find a long stone wall between 6 to 8 meters (20-25 ft) high and about 90 cm (3 ft) strong. Here in the border region between Germany and Austria, partly hidden by the mountainous forest the ruins of an old and massive barrier can be seen along the flank of the mountain. It's not quite visible from the street in the valley below and current aerial imagery only shows a densely wooded area. Back in 1805 Napoleon's troops used a nearby mountain path now known as Franzosensteig (literally "French path") to bypass this fortification.