The Burren is literally littered with archaological sites dating as far back as the mesolithic period (7000 to 4000 BC) and spanning pre-historic and historic period up until the medieval period (late 12th to early 16th centuries AD). There are some very impressive sights that are well known, such as the Poulnabrone portal tomb which shold not be missed on a trip to the area. Equally interesting is to forge through unmarked territory to find little explored cairns, villages, churches, tombs, castles and ring forts. The adventurous will find some remarkable sites.