Hochvogel

The Hochvogel consists of folded and thrusted upper Triassic dolomite known as either the Main Dolomite or Hauptdolomit. The Main Dolomite is composed of decimeter to meter scale beds of brittle, variably bituminous, dolomite and marl. Within the summit area, these strata dip 20° to the north-northwest. These strata are tectonically stressed and highly weathered. In addition, they are intensely fractured perpendicular to the bedding. This rock package was overthrust over younger rock strata during the course of Alpine mountain folding as part of the Lech Valley Nappe (Lechtaldecke). The highest and most striking mountains in the Allgäu Alps are all made of this rock.^[2][3]

A large fracture that is 2 to 6 m (6.6 to 19.7 ft) wide splits the summit of the Hochvogel. This fracture is traceable more than 60 m (200 ft) below the summit along the steep, mountain steep, sides. It has trapped boulders inside it about 10 m (33 ft) deep within it. This fracture divides the mountain into a stable northwest flank and a highly unstable southeast flank. During the last century, the unstable southeast flank has dropped by about 3 m (9.8 ft) downward relative to the top of the edge of the stable northwest flank. Smaller lateral fractures separate the mountain into additional unstable blocks of rock.^[4]

The presence of large fractures in the summit of Hochvogel was first recorded in 1869. In 1934 and 1935, small rockfalls occurred within the southwest flank of Hochvogel. In the 1970s to 1980s, a observable summit crack had appeared, but it could be still easily stepped over at that time. During 2005, 2007, and 2016, additional southwest flank rockfalls occurred. In 2010, the ever-lengthening summit crack had reached both edges of Hochvogel's summit plateau. By 2018, the main summit fracture had opened by 2 to 4 m (6.6 to 13.1 ft) in width to become 5 m (16 ft) wide and 30 m (98 ft) deep and continued to move by a few millimeters per month. The downslope movement of the rock underlying the unstable southeast flank of Hochvogel has caused it to become severely fractured. This movement deepened the summit fracture to a depth of 60 m (200 ft) by 2024. The inevitable catastrophic failure of the summit fracture along a failure plane composed of two large, fracture systems could result in either a single rockslide or series of progressive rockslides involving as much as an estimated 260,000 m3, even 300,000 to 400,000 m3, of rock.^[5][6]

The older, now out-of-print editions of the Alpine Club Guide (Alpenvereinsführer) for the Allgäu Alps state that the mountain was first climbed a long time ago. A shepherd's boy from Hinterhornbach is said to have already climbed it as early as 1767.^[7] In 1818, the surveyors supposedly found a ruined cairn at the top.^[8] The first ascent was at least as long ago as 1818, when the Allgäu Alps were surveyed and the Hochvogel summit was used as a triangulation point.^[9] However, when a man named Trobitius from Kempten climbed the peak in 1832, some of his fellow townsfolk refused to believe him as the mountain was still considered unclimbable by many.^[10]

One of the most notable touristic climbs was by Hermann von Barth, who stayed overnight at the summit in 1869. On 19 July that year he started off from Sonthofen in the morning and reached Hinterstein, travelling exclusively on foot, where he took a midday rest around 12 o'clock before continuing. Passing the Bärgündlealpe alps, the Balkenscharte saddle and the Kalter Winkel he reached the summit of the Hochvogel at around 8 o'clock in the evening. On the next day he climbed south on the eastern side of the south-southwestern arête into the Rosskar cirque and continued down to Hinterhornbach. On that day he arrived at the confluence of the Schwarzwasserbach and the Lech, where he stayed in an abandoned Alpine hut. The next day he walked via Weißenbach and the Gaicht Pass to Nesselwängle, climbed the Aggenstein and overnighted in Schattwald. On the fourth day of his great tour he returned to Sonthofen in the morning.

The side of the Hochvogel lying on German territory, including the neighbouring mountains and valleys, is part of the Allgäu High Alps Nature Reserve. On the Austrian side there is no nature reserve near the summit. The bottom of the Hornbach valley, which borders the Hochvogel to the south, together with large parts of the Lech valley and its side valleys was designated on 1 December 2004 as the Tyrolean Lech Nature Reserve. It has an area of 41.38 km² (15.98 sq mi).

The view from the top is vast and grandiose, encompassing many of the peaks in the Allgäu Alps as well as those in the neighbouring Lechtal Alps to the south. To the east, the view extends over other chains in the Northern Limestone Alps as far as the Wetterstein and Karwendel. To the south, a panorama of the central Alpine ridge opens up from the High Tauern across the Zillertal, Stubai and Ötztal Alps to the mountains of the Albula and the Silvretta. To the west, the Swiss Alps - the Alpstein (Säntis) and the Glarus Alps (Tödi) can be seen. And, to the north, the view extends far beyond the Swabian Alps to the Black Forest and the Swabian Jura. The best views tend to occur in the autumn and winter rather than in spring and summer.

On 14 December 1945 an American Flying Fortress (a four-engine bomber) crashed on the western flank of the Hochvogel. The aircraft came from Belgium and actually intended to land at the Lechfeld Air Base. The accident killed all six crew members. their remains could not be retrieved until months later because of their location on steep slopes and heavy snow.^[12]

According to the United States Air Force the accident was due to a navigation error when the aircraft flew into a snowstorm. The wreck of the machine was dismantled in the 1950s and carried away.

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  Northern aspect from the Jubiläumsweg
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  Southern aspect with the Kaufbeurer Haus and Hornbachtal
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  Southern side of the summit from the Kaufbeurer Haus
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  From Hinterhornbach