Schwarze Lacke - Neustücklgrotte

Useful Information

Location: Between Hieflau and Eisenerz.
(Katasternummer: 1741/6)
(47.581777, 14.825451)
Open: no restrictions.
Fee: free.
Classification: KarstKarst spring
Light: n/a
Dimension: Yavg=524 l/s, Ymax=10,000 l/s, Ymin=50 l/s, A=585 m asl, L=1,084 m, VR=112 m, T=7 °C.
Guided tours: self guided
Photography: allowed
Accessibility: no
Bibliography: Robert Seebacher (2005): Zwischenbericht über die aktuellen Forschungen in der Schwarzen Lacke bei Eisenerz, Steiermark, In: Verband Österreichischer Höhlenforscher, Verband der deutschen Höhlen- und Karstforscher e.V. (Hrsg.): Die Höhle – Zeitschrift für Karst und Höhlenkunde. Band 56, Nr. 1–4, 2005, ISSN 0018-3091, S. 90–95 pdf
J. A. Nagel (1747): Beschreibung des auf Allerhöchsten Befehl ihro Maytt: Des Röm. Kaysers und Königs Francisci I. untersuchten Ötscher-Berges und verschiedener anderer im Herzogthume Steyermarck befindlich, - bishero vor selten und verwunderlich gehaltener Dingen Österr. Nationalbibliothek, Handschrift Nr. 7920
Address: Wassermannsloch
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


1747 first speleologic exploration by Joseph Anton Nagel.
1950er first dives by Johann Resch sen. from Eisenerz.
1982 dives by W. Schierl, I. Luks und K. Stifter.
1995 explored by the project Aquarius from the Verein für Höhlenkunde in Obersteier.
1996 cave diving forbidden by owner.
2001 area purchased by Dr. Hans Riegel, owner of „Haribo“, who allowed further research.


The Erzberg (ore mountain) consists of iron ore and is mined for hundreds of years. Until today, it is the financial backbone of the area. According to legend it was discovered after a fantastic event.

A group of fishermen once threw a net into the nearby Leopoldstein Lake. After some time they pulled it out of the water and found a Wassermann (water man, water sprite) in the net. Out of fear they tried to kill him, but the water sprite asked them not to kill him. He offered them 100 years of gold, 1,000 years of silver, or never ending iron. The fishermen chose the iron and the waterman pointed to a mountain and vanished into the water. So the men discovered the Eisenberg, but the waterman went back into the Wassermannsloch and was never seen again.

The Wassermannsloch (Water Man's Hole) is a resurgence also known as Schwarze Lacke (Black Puddle). The water is flowing out of a water-filled cave named Neustücklgrotte, which is explored by the cave divers of project Aquarius from the Verein für Höhlenkunde in Obersteier. This cave is surveyed for 1084 m, it is the longest cave in Austria to be surveyed behind a permanent siphon [2014]. The spring is the most important karst spring in the southwest of the Hochschwab massif (a funny characterization cited from the report by Robert Seebacher 2005). For this reason it was visited by Joseph Anton Nagel in 1747 who later wrote the first scientific or speleologic report about the cave. He was an envoy of the Austro-Hungarian emperor and travelled throughout the empire writing descriptions of curiosities and beauties he discovered. But that was the last exploration for a long time.

The cave is water filled immediately after the entrance, so any exploration requires cave diving. When the technical means were first developed in the 1950s, divers all over the world started to explore water-filled caves. Here it was Johann Resch sen. from Eisenerz, who started cave diving. Supposedly, he already managed to dive through the entrance siphon for the first time with a self-made diving device. And over the years numerous divers went into the cave.

The most detailed exploration was made between 1995 and 2006 by the cave divers of project Aquarius. They are members of the Verein für Höhlenkunde in Obersteier, which is the responsible caving club for this area. They surveyed the cave and created a 3D model. There was a setback though, the spring is privately owned and the owner revoked his permission for diving after the first year of intensive research. We do not know the reason, but normally it's a problem of liability. Maybe he just got nervous because there was the danger of a diving accident. The problem was solved after 5 years when the area was bought by Dr. Hans Riegel, owner of the famous German sweets company Haribo, who allowed research. Haribo is the abbreviation of Hans Riegel Bonn, by his father and founder of the company. An expanded 12-member team consisting of divers, scientists and helpers was assembled to ensure effective documentation of the cave. The research project ended in 2006 when all leads were explored.

Behind the 180 m long and 27 m deep entrance siphon lies an extensive air-filled passage system. There is a second siphon which may be bypassed by a higher, dry passage. The cave system ends at a third siphon, which has not been explored so far. The cave has mostly phreatic profiles, formed along layer joints and SW-NE striking fissures.

The spring is perennial, even during prolonged frost or severe drought the discharge rarely drops below 80 l/s. Nevertheless, the flow changes strongly over the year and may reach 10,000 l/s at snow melt or after heavy rains. This is a typical seasonal karst spring. The catchment area of the spring is not exactly known, it probably extends from the Hochblaser (1771 m asl) to behind the Kaltmauer (1929 m asl).

The Erzbach originates from the huge open cast mine Erzberg. It grows with numerous tributaries from the side valleys and flows through the town Eisenerz. About 1 km down the valley from the town is the Leopoldsteiner See on the right side of the valley, its outflow is called Seebach and is also a tributary of the Erzbach. At the confluence the valle narrows, becomes almost a gorge which is just wide enough for the river, the road and the railroad line, surrounded by steep walls on both sides. About 4 km from the town is the Wassermannsloch, and due to the limited space there is no possibility to stop your car. There once was a small parking lot, which was closed down for security reasons, the road has heavy traffic and parking cars and people walking on the road was quite dangerous. The only possibility to park your car is 600 m down the valley, then you have to walk back 600 m on a wooden walkway which is separated from the road by a railing. There is a bridge across the river and a trail to the spring. A visit will take about 20 minutes walking time plus about 15 minutes to see the spring. The spring is quite spectacular and definitely worth the effort.