Looking west across the earthworks;on the rhs is the motte,to the lhs of the wooden bridge,is the eastern bailey defensive mound/wall.Beyond the curved footbridge can be seen the west bailey mound/wall.
see http://www.ecastles.co.uk/castleacre.html
see http://www.castlexplorer.co.uk/england/acre/acre.php#castle
see http://www.castleuk.net/castle_lists_east_anglia/132/castleacre.htm
Just look at the enormity of these works and remember ,it was done by hand,by the average Saxon serf/slave,at the new Norman LORD'S BEHEST.Literally,do it or else.