Grotten St. Pietersberg

Maastricht Caves

Useful Information

Location:	Maastricht. Grotten Noord: departure from Luikerweg 80, district 12, Maastricht. Grotten Zonneberg: departure from Buitengoed Slavante, 1 Slavante, Maastricht. Follow the narrow path uphill along the ENCI plant.
Open:	Grotten Noord: All year daily afternoon. Grotten Zonneberg: All year Sun afternoon. Exact times see online booking. Post-pandemic Aftermath [2022]
Fee:	Adults EUR 9.50, Children (4-11) EUR 7.95. [2022]
Classification:	Rock Mine marl mines World War II Bunker
Light:	Incandescent Electric Light System
Dimension:	T=9-10 °C.
Guided tours:	D=60 min.
Photography:	allowed
Accessibility:	no
Bibliography:
Address:
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.

History

1700	fortress built on the hill.
1770	head of a reptile, the Mosasaurus, fund.
1794	fortress attacked by the French, caves used for shelter.
1942-1945	the famous Nightwatch of Rembrand was stored here.

Description

The Grotten Sint Pietersberg (Caves of Mount St. Pieter) are actually no caves, as they are not natural. This man made subterranea are former limestone quarries, or better limestone "mines" as they are underground. The limestone was used for various purposes like burning lime for white colour or making cement for mortar. This obviously works only with pure limestone. But the limestones are interbedded with marls and marlstones. So the quarrying started at the surface at the outcrops of the high quality limestone. At some point it made no sense to mine enlarge the quarry because it was surrounded by marl, instead they followed the dipping limestone layer underground.

The rock was mined in huge caverns, but the miners had to leave columns of marl to sustain the ceiling. This ancient mining method is called room and pillar method. The result is a maze of rectangular flights of columns and long corridors. The limestone is a sea sediment which contains numerous fossils. The fossils of a Mosasaurus and a giant turtle found in the caves of Mount St. Peter are now on display in the Narural History Museum of Maastricht.

The walls of the caverns are covered by drawings and names, visitors left their name and the date of the visit. Today this behavior is considered at least impolite, sometimes even vandalism. But 300 years ago it was just natural to leave a trace. During World War II the caves were equipped as air raid shelter, they were prepared to shelter 50,000 people. The Grotten Noord were never used, but the Grotten Zonneberg were uses . During the 20th century artists used the cave walls officially for their works.

Today there are two different parts of the cave open to the public, Grotten Noord (Northern Caves) and Grotten Zonneberg (Zonneberg Caves). Both are located to the south of the city, inside a hill called St. Pietersberg (120 m asl), hence the name Grotten Sint Pietersberg.

The tours through the Grotten Noord are the main tour of the Maastricht Underground. They are offered all year daily, there are multiple tours every day about 2/3 in Dutch, the other in English. Unfortunately we are not able to give exact times as the times change frequently. This is a result of Corona restrictions, the booking is made solely online through their website, where you can see the actual dates and times. Beneath the tours for individuals there is the possibility to make a private tour after appointment, at least 10 days in advance. The tours are lead by Official Maastricht Guides.