The "DRIEDAGEN/WALENBERG"( three days / french quarry) is a quarry that is part of the Roos Burg. The French quarry was on Liège territory, hence the name.But access was on Limburg(province) territory. The "Three Days "got its name to that in 3 places daylight came. It was in 1962 almost separated from the rest by a collapse,only through a climb overby the collapse is still the only connection. The surface area covers approximately 200 by 500 meters.This was much in use as mushroom farming, until a few years ago,after reinforcements were made for safety.