Despite appearances,this is a relatively small castle,in a commanding position overlooking the Don valley.The keep only has two rooms,with stairway access to the top of the keep.(136 steps from bailey to the top of the keep)
SEE http://www.ukheritage.net/castles/castle_acre.htm (THERE'S A REFERENCE TO CONISBROUGH)
see http://www.english-heritage.org.uk/server.php?show=nav.17413
see http://www.castlefacts.info/contentpages/castledetails/castledetails.asp?country=England&countyid=50&county=Yorkshire West Riding&castleid=4463&latitude=53.4843711853027&longitude=-1.22572994232178&uin=10904