More information on this cave, by those exploring it, can be found on the Landesverein für Höhlenkunde in Oberosterreich site, with text available in both English and German and with a number of excellent photos.

Altitude:

55 a Durchgang Fensterhalle 1532 & 1539m
55 b Bärenhöhle 1547m
55 c Neuer Eingang 1563m
55 d Grundloch ("Brunnen") 1544m
55 e Schacht I 1570m
55 f Schacht II 1547m
55 g Schacht III 1560m
55 h Schneegrube 1540m
55 i Schacht IV (Pilzlingschacht) 1560m
55 k Obere Himmelspforte 1630m
55 l Untere Himmelspforte 1593m
55 m Durchgang Feistor 1540m
55 n Einstieg Altausseergang 1553m
55 o Planer-Eishöhle 1470m
55 p Humuspforte 1635m
55 q Gigantenkluft 1518m

Location: NE of Hinterer Raucher

There are seventeen entrances, of which the highest is at 1635m. This gives the cave a vertical range of -718m, +7m, total 725m.

The cave had been surveyed to 6000m long and -216m by 1965. An Austrian National expedition in 1965 reached -530m. A sump in the Hinterland at -538m was reached in 1966, when the length was over 10.3 km. In 1970, Großen Rundgange and Ischler Esteiler brought the length up to 16.3 km. In October 1973, the Dunkler Grund area led to -718m, (-723m in some sources) at which time the length was 18km. In 1975 the system was connected to the nearby Planer-Eishöhle. The length in January 1976 was 19052m and in December 1977, 20155.5m. Sektion Ausseerland journal gave 23900 m in July 1980. Spéleo Flash number 128 gives 16 entrances and a length over 30km. Die Höhle 1986(3) gives 747m, 40km, which is about the same as LVHK Steiermark Journal for 1984, which states length 40.2km, depth 746m as at the end of 1984. The World Deep/Long caves list (end 1995) from Bob Gulden of the NSS Geo² Long and Deep caves committee gives 70km and 725m, quoting BCRA Caves & Caving number 44, p 47 as its source (Summer 89).

The labyrinthine system contains several levels of development, mostly southwards towards Nagelsteghöhle (the probable resurgence at 850m). The current deepest point (a sump) has been reached by systematically traversing over pitches of 40 to 90m.

Exploration: Under the aegis of LVHK Oberösterreich, 1961-present,
Austrian National expedition took place in 1965,
Both LVHK Oberösterreich and LVHK Steiermark worked together in 1973.

References :

78.2012

(GSAB) Spéalp 1 (June 1977) pp 33-49, Totes Gebirge : Description des principaux gouffres de la zone ouest du massif, Jean Claude Hans & Etienne Degrave
English Translation
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