Ründerother Höhle

Useful Information

Location: Im Krümmel 39, 51766 Engelskirchen.
A4 exit Engelskirchen, 1 km W Ründeroth, on the right shore of river Agger.
(50.993620430142830, 7.449468326800911)
Open: APR to 01-NOV Thu-Sun, Hol 10-17.
Tours 10, 11:15, 12:30, 13:45, 15, 16:15.
Fee: Adults EUR 6, Children (3-15) EUR 4, Family (2+*) EUR 20.
Groups (10+): Adults EUR 5, School Pupils EUR 3.50.
Classification: SpeleologyKarst cave lower middle Devon (reef limestone)
Light: LightLED Lighting
Dimension: L=1,071 m, VR=31 m, BC: H=18 m, T=6-8° C.
Guided tours: L=260 m, D=45 min.
Photography: allowed
Accessibility: The entrance hall and main corridor can be accessed by wheelchair.
Bibliography: Maximillian Dornseif, Stefan Voigt (2020): Die Höhlen am unteren Walbach, In: Der Antiberg. Band 75, 2020, S. 33–41. DOI Deutsch - German
Dieter W. Zygowski (1983): Die Aggertalhöhle in Ründeroth, Gemeinde Engelskirchen, Oberbergischer Kreis, Hrsg: Verkehrsamt der Gemeinde Engelskirchen, 1983 Deutsch - German
Hans-Werner Holz (1960): Geologie der Höhlen von Ründeroth und Wiehl und ihrer Umgebung (Rheinisches Schiefergebirge), In: Decheniana. Nr. 113, 1960, ISSN 0366-872X, S. 1–38. Deutsch - German
Hans Maassen, Franz Lotze (1953): Die Aggertalhöhle in Ründeroth (Oberbergischer Kreis). Ihre Geschichte und Beschreibung, Verkehrsamt des Luftkurortes Ründeroth, Ründeroth 1953. Deutsch - German
Address: Führungsbetrieb Aggertalhöhle Ründeroth, Dr.-Ing. Sylvia-Kathrin Tanneberger, Löh 4, 51709 Marienheide.
Aggertalhöhle, Im Krümmel 39, 51766 Engelskirchen, Tel: +49-2263-70702 (ticket office, answering machine). E-mail: contact
Kulturamt der Gemeinde Engelskirchen, im Rathaus, 51766 Engelskirchen/Ründeroth, Tel: +49-2263-83-137.
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.


1773 mentioned as year of discovery in old documents.
1819 a Feckelsberger Höhle first noticed. Very likely the Aggertalhöhle.
1890 tunnel into the cave built.
1910 first cave map by Benno Wolf.
1927 start of development with paths and electric light.
12-OCT-1930 inauguration of the show cave under the name Felsen- und Muschelhöhle.
1945 used as air raid shelter at the end of World War II.
1948 reopened.
1950 renamed Aggertalhöhle by the Gemeinderat (municipal council).
1952 tunnel redone with concrete.
1960 cave map by Hans-Werner Holz.
1967 Annual conference of the Association of German Cave and Karst Researchers (VdHK) in Ründeroth.
1980 Celebration of the 50th anniversary as a show cave.
1981 Annual conference of the Association of German Cave and Karst Researchers (VdHK) in Ründeroth.
1995 cave run by the Arbeitskreis Kluterthöhle e.V..
2021 renovation of the cave and installation of an LED lighting system.


The Aggertalhöhle is a very dry cave. A layer of clay is sealing the cave from water above, so there is no dripping water and thus obviously no dripstones. Only after heavy rains, the water enters the lower part of the cave and floods them. On several locations the cave has nice speleothems of aragonite. Brushes of fine needles, only a few millimeters long, sit on the walls. Other speleothems are a few small sinter formations, also consisting of aragonite. The reason why the speleothems are aragonite and not calcite is the high amount of Magnesia (Mg) in the dolomitic limestone.

Very interesting are the fossils in the limestone, a tropic reef complex is fossilized and the various petrified lifeforms are brought out by erosion. On a walk through the cave the visitor sees various regions of the reef, the outside with corral blocks destroyed by the surf, and fine-grained sediments of the lagoon. A particularly funny highlight is the Pastorengang (Pastor's Passage), which is only 30 cm wide in some places. When the cave was first made accessible through a gallery in 1890, a pastor who was visiting the area learned about the cave. He was so interested that he wanted to explore all the passages of the cave, including this one, which the workers advised him against. As expected, the rather well-fed clergyman got hopelessly stuck and could only be freed after much effort. He must really have been very obese, the passage can be navigated quite easily even by overweight people, many more visitors actually have problems with claustrophobic attacks. Fortunately, the narrow passage can be easily bypassed.

The Aggertalhöhle was discovered as early as the 18th century, but was not mentioned in a document until 1819 under the name Feckelsberger Höhle (Feckelsberg Cave). It was rediscovered during mining activities for iron ore and named after the village of Feckelsberg, which is only a few hundred metres away. The entrance to the cave is at the point where a dry valley branches off to Feckelsberg. It was also known as Ründerother Höhle (Ründeroth Cave), Ründeroth is the nearest larger town, about the same distance away on the banks of the Agger River. The entrance was originally at the bottom of a deep sinkhole until a horizontal access tunnel about 30 m long was dug in 1890. At that time, the land belonged to the Cologne industrialist Theodor Guilleaume and so the cave was named Guilleaume Cave. In 1910, it was explored by the speleologist Benno Wolf, who drew the first, still quite simple plan of the cave. In the 1920s, the industrialist Otto Wolff became the new owner, and he had the dilapidated tunnel renovated and organised festivities in the cave, which was lit with pitch torches. Between 1927 and 1930 it was developed into a show cave by the Verschönerungsverein Ründeroth, on 12-OCT-1930 it was opened as a show cave under the name Felsen- und Muschelhöhle (Rock and Shell Cave). It was not until 1950 that the cave was finally renamed Aggertalhöhle (Agger Valley Cave) by decision of the local council. A beautiful name with recognition value, which obviously goes back to the Agger River flowing through Ründeroth. However, the entrance is not in the valley of the Agger, but in a side valley through which the tributary Walbach flows.

Only a relatively small area around the cave is built of limestone and karstified. The surroundings consist of greywacke and schist, the limestone is the center of a saddle. The karst area was declared a natural monument with a size of about 50 hectares. It shows several other karst features, despite the cave. There are eight more caves known in the area and there are several karst springs and sinks. The most important cave in the area is the Windloch (Wind Hole), which was discovered in spring 2019 by the Arbeitskreis Kluterthöhle (Klutert cave working group) in nearby Mühlenberg. With a total passage length of over 8,500 m, it is the largest cave in the area and its discovery led to a media response which resulted in an increase in the number of visitors to the Aggertal Cave.

Only 40 m from the entrance to the Aggertal cave, the Walbach flows. This brook drains the area, it is a tributary to the Agger river. Around the cave, the Walbach brook shows several interesting geological features. It is higher than the cave, but there seems to be no connection, as the water does not enter the cave. But there are several sinks in the bed of the brook, which sre connected to nearby springs. The detailed hydrological situation was explored with dye trace experiments.

Since 1995, the cave has been under the scientific care of the non-profit Arbeitskreis Kluterthöhle e.V. (Klutert cave working group). They first resurveyed the cave and a new cave plan was drawn up in 1997. In summer 2021, the show cave was thoroughly renovated and equipped with LED lighting. This has significantly improved the tour, on one hand much has been revealed by the renovation and on the other hand it has been put into perspective by the new cave lighting.