Orval is a trappist monastery in southern Belgium, where the monks still make beer (there are only 6 trappist monasteries left in the world, 5 of them in Belgium). In fact, its my favourite beer amongst all the ones I have tried...
The monastery itself was destroyed during the French revolution, and only rebuilt in the early 20th century. You can visit the ruins of the ancient monastery, but not the grounds of the modern one where priests lead a life of prayer and work. They make a lighter beer for their own consumption, and they also make a very good cheese...