Chimay is one of the seven Trappist beers.
A Trappist beer is a beer brewed by or under control of Trappist monks. There are a total of 174 Trappist monasteries worldwide (as of April 2011); only seven (six in Belgium, one in the Netherlands) produce Trappist beer and are authorized to label their beers with the Authentic Trappist Product logo that indicates a compliance to the various rules of the International Trappist Association. (from Wikipedia)
Here’s a look inside Chimay: