Marl exploitation

The Limburg chalks or 'mergel' have been excavated since time immemorial. Pliny the Elder (23-79 AD) in his 'Naturalis Historiae' wrote that in northwest Europe the Eburones had already found a way of fertilising the land by using local chalks. Pliny even referred to mining shafts 100 feet deep or so.

Earlier still Marcus Terentius Varro (116-27 BC) had written in his 'De Re Rustica' that Roman armies approaching along the Rhine had come across areas where the local population fertilised their fields by using excavated white chalk. It cannot be ruled out that those who constructed the flint mines at Ryckholt-St Geertruid almost 4000 years ago also used the 'mergel' in this way: nowhere in the region is there a trace of the enormous amounts of chalk which resulted from excavating the mine shafts. The Romans introduced the use of local rock types for building houses, farms, thermae and fortifications. In southern Limburg chalk was used, but not in large quantities.

After the Roman era the use of 'mergel' as a building stone declined rapidly: people returned to using loam, timber and straw. In the case of Mount St. Pieter, the oldest sections of the galleries probably date back to the beginning of the fifteenth century. At that time, Johan van Heinsberg (1417-1435), the prince-bishop of Liège, requested the local monks to start the exploitation of chalk blocks to help the city of Liège repair damages sustained during war. Only from 1580 onwards was this work taken up by self-employed 'blokbrekers'.

Over the centuries this resulted in a system of galleries with a total estimated length of more than 250 km !

The end of the 19th century saw the start of open-cast mining, with the extracted 'mergel' being used for cement production. Guided tours of the remaining parts of the former galleries (Lichtenberg and the Northern galleries) are organised by the Maastricht tourist office (VVV).

home | back