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21 The Moosberg tunnel


struck:        1577 (together with Matthias tunnel)

leaving:               Hired 1586, abandoned 1690

Elevation:       625 meters (m)

overall length         312 sticks (372 meters)

worker:                  only sideways hope and sink works

Naming:   former area designation upper Mooseck , today Obereck


With the first tunnels driven into the Ischler Salzberg, only short and poor salt deposits could be driven in both the Lauffner salt dome (1563 Mitterberg tunnel, 1567 Alter Steinberg tunnel) and the Perneck salt dome (1567 Lipplesgraben tunnel, originally Obernberg tunnel). Therefore, from 1577, an intensive search for further salt deposits on the Ischler Salzberg began.

Detailed information about the intensive search for salt at that time can be found in Anton Dicklberger's Salina History of Upper Austria from 1817.


On October 31, 1577, by order of the salt official Christoph Haiden, an inspection was held at the Ischler Salzberg by salt mining officials.

As part of the inspection, a new tunnel dug in 1577 on the upper Moosegg in the forest of Hans Reicher to examine a salted lake was driven through. However, with a total length of 10 rods (11.9 m), this only penetrated 3 rods (3.6 m) of well-salted medium , which also carried acidic water.

In 1577 the new tunnel was given the name Moosberg tunnel .

In 1580, the Salzamtmann Christoph Haiden again inspected the Ischler Salzberg. At the same time, the further advance of the field location of the main shaft of the Moosberg tunnel was discussed, since only 11 sticks (13.1 m) of salted rock were exposed in this tunnel.

In 1583, at the quarterly Haeuer measurement, it was decided to lengthen the 11 bar (13.1 m) long salt medium found in the Moosberg tunnel, where the main shaft had still been worked in vain in the deaf mountains, to search for the salt store and to examine the same with a sink work in depth.


In 1584, two inspections were even carried out to establish rules with regard to an appropriate exploration of the Ischler Salzberg.

Although no other salt rocks could be found in the Moosberg tunnel apart from the 11 Stabel (13.1 m) long salt medium, due to all hopes pursued sideways and in depth, the inspectors decided, despite these circumstances, to continue the advantageously located tunnel operate. Because of the traces of salt found both above and inside the tunnel, the hope of finding a rich core mountain was not given up and it was decreed that the deserted field site of the main shaft should be continued towards the ridge of the mountain after twelve hours (to the south).

In the hopefully continued operation of the Moosberg tunnel, there was a strong inrush of water at the field location of the main shaft made of fissured rock. Since the necessary amount of brine could not be produced in the long term with the tunnels previously dug at the Ischler Salzberg and the hope of finding a new salt store in the Moosberg tunnel had to be given up, it was decided in 1584 to dig a new investigation tunnel at the Roßmoos.

In 1584, the inspectors also suggested lowering the sinkage from the deepest point in the Moosberg tunnel, which had been operated in vain for 8 years now, by a further 14 rods (16.8 m) towards the depths


The inspectors were of the opinion that in the area of the Moosberg tunnel there was a salt mine that had been in use for many years and is now rotten . By further lowering the sink works, one was convinced that areas of the salt mountains could be reached that could not be reached long ago. Contrary to expectations, no existing salt mountains were opened up with this newly sunk section.

Anton Dicklberger thinks the suspicion of an old salt mountain at Moosegg is very unlikely. No traces of older, abandoned buildings were found when the Moosberg tunnel was being excavated. Although a saltworks near Ischl is mentioned in some old documents, it seems more likely to Dicklberger that this was not operated at Moosegg but in Pfandl near Ischl.

On February 11 and 12, 1586, another mountain survey was carried out on the Ischler Salzberg with the involvement of several mountain experts from the salt works in Hallstatt, Aussee and Ischl.

Since the salt mountains had been excavated over a whole mountain thickness by the test digging operated by the Matthias tunnel, the new mining tunnels on Moosegg and Roßmoos , which were more than uncertain in terms of success, were finally discontinued.

The Moosberg tunnel, operated with great hopes between 1577 and 1586, was extended to a length of probably 120 Stabel (143 m). Only 11 sticks (13.1 m) of salt agents could be found.

The Moosberg tunnel was probably occupied with interruptions in the following 103 years from 1586 to 1690. The main shaft of the Moosberg tunnel with a smaller profile was lengthened by a further 192 bars (228.9 m) to a total of 312 bars (371.9 m). Shortly before the attack on the Rabenbrunn tunnel, which was also driven towards the Lauffner salt dome in 1692, the Moosberg tunnel was finally abandoned in 1690 and left to decay.

Because of the good stability of the surrounding mountains, a large part of the main shaft of the Moosberg tunnel has been preserved to this day.

The Moosberg tunnel was popular with adventurous young people up until the 1970s. The remains of a raft that was built to cross the water dam and some signatures in the clayey mountains bear witness to this to this day. By the mid-1980s at the latest, the mouth of the Moosberg tunnel had completely rolled up.

In August 2018, Horst Feichtinger uncovered the entrance to the tunnel after extensive, manual digging, so that it was possible to drive on it. On August 14, 2018, members of the IGM (Mitterbergstollen interest group) and the landowner carried out an extensive tunnel inspection, including photographic documentation of the still accessible mine spaces.

The approximately 430-year-old Moosberg tunnel is the oldest, still drivable mine building in the Ischler Salzberg, which is in its original condition. The tunnel, made with hammers and iron work, is a first-class mining monument with its unique sinter formations for the Ischler Salzberg. Due to the great importance of the Moosberg tunnel, the IGM decided in September 2018 to clear the main shaft up to the sintering at tunnel meters (Stm.) 82 to 92 and thus make it accessible for interested visitors.

The tunnel, which was completely hand-carved and is still passable over a length of 221 m, was driven south-east from the anchor point at 625 m above sea level, following the mountain ridge.

The standard profile of the tunnel is around 190 cm high, 80 cm at the top and 120 cm at the base.

The first 7 pieces had to be made of wood when it was recaptured. From Stm. 7 to 25 the tunnel was driven in stable layers of lime. The standard profile in the front section of the tunnel is around 1.9 m in height and 0.8 m in roof width and 1.2 m in bottom width. From Stm. 25 the limestone layers merge into the pebbly, thick-banked marl limestone of the Rossfeld layers.

The sandstones and conglomerates of the Rossfeld Formation were deposited in the early Cretaceous period around 120 million years ago. During deposition, massive undersea mass movements with mudslides and debris flows took place. The layered deposits with a chaotic structure made of older limestone boulders and hazel rocks, which geologists call olisthostromes , can also be found in the Moosberg tunnel.

At Stm. 35 there is an approx. 0.5 m thick clayey deposit. In this clayey breccia one finds bluish violet clays that indicate leached Haselgebirge. The storage was cleared up to a height of approx. 3 m in the course of the original tunnel excavation. At Stm. 39 one finds another clayey intercalation with a total thickness of 1.8 m and finally at Stm. 59 a third intercalation also containing Haselgebirge stones with a thickness of approx. 1.0 m. The thick banked marl layers in the area of the last two deposits are heavily sintered.

The extensions and sink works mentioned by Dicklberger were probably created in the area of these 3 deposits, since the leached Haselgebirge stones were interpreted as a sure sign of salt-bearing mountains.

From Stm. 65, an extensive waterlogging began behind a collapse cone. The remains of a raft built in the 1970s, which was used to cross the tunnel lake, which was up to 1 m deep in rainy times, were found in this area. Unsuccessful attempts to cross the tunnel lake on stilts have also been handed down. In the course of the demolition work, the massive collapse cone from Stm. 57 to 65 was completely cleared out and the waterlogged was drained.

From Stm. 65, the in-situ, stable marl layers become thinner. The strong water flow in this area has led to massive sintering. The wooden stamps built in to protect against dripping water from Stm. 82 to 92 are still clearly visible today. Most of the pit wood has decomposed over the centuries, but the impressive sinter imprints have survived to this day. A standard profile of 1.7 m line height and 0.6 m ridge and 1.0 m bottom width can be reconstructed for this section from the expansion remains.

From Stm. 99 there are thin layers of marl and Schrambach. The Schrambach layers were also deposited after the Rossfeld layers in the early Cretaceous period. The rust-brown weathered limestone marl is tectonically overprinted. Clearly recognizable armored areas as well as staggered layers of mylonite bear witness to massive mountain movements. Due to the disruption of the marl structure, from Stm. 99 more and more collapses occurred. From Stm. 127, the marl becomes thicker again in a much more undisturbed bed and thus also more stable.

At Stm. 130 there is a clear bend in the route towards the south. This change in the direction of tunneling is likely to be due to the specifications of the inspection of 1584.

Due to the now stronger water flow, you will find extensive sinter terraces with some water ponds on the sole. In some cases there are clearly visible trace nail residues in the sinter.


At Stm. 143 there is an impressive narrowing of the driven route profile to 1.8 m route height and 0.6 m ridge and 0.8 m bottom width. Presumably, here in 1586 the drive of the main shaft of the Moosberg tunnel ended for the time being. In the 104 years that followed, until the drive was finally shut down in 1690, the smaller route profile was chosen for cost reasons for the following tunnel section.


From Stm. 140 to 197 are the stable, partly chert-bearing limestones of the 150 million year old Oberalmer strata from the late Jurassic period.

From Stm. 197 you can find layers of marl again in the hanging wall of the Oberalmerkalke. The thick banked marl layers that are now present are tectonically heavily overprinted. Due to the flat bedding, massive ridge collapses occurred on mylonite layers and fissure areas.


From Stm. 221 the route is currently completely broken. A further advance into the main shaft of the Moosberg tunnel, which is about 150 m long, would only be possible after extensive clearing and securing work.


Above ground, north-west of the mouth hole, the extensive slag heap is still clearly visible. With an average crown width of 2 m, this is almost 27 m long and approx. 6 to 7 m high at the end of the heap.



Sources used:

Dicklberger Anton, Systematic history of the salt pans in Upper Austria, Volume I, Ischl 1817, Transcription by Thomas Nussbaumer, Weitra 2018.

Schraml Carl, The Upper Austrian salt works from the beginning of the 16th to the middle of the 18th century, Vienna 1932.

Schiendorfer Leopold, Perneck - A village through the ages, Linz 2006.



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