Birmingham is dominated by the Birmingham Fault, which runs diagonally through the city from the Lickey Hills in the south west, passing through Edgbaston and the Bull Ring, to Erdington and Sutton Coldfield in the north east.[110] To the south and east of the fault the ground is largely softer Mercia Mudstone, interspersed with beds of Bunter pebbles and crossed by the valleys of the Rivers Tame, Rea and Cole and their tributaries.[111] To the north and west of the fault, between 150 and 600 feet (46 and 183 metres) higher than the surrounding area and underlying much of the city centre, lies a long ridge of harder Keuper Sandstone.[112][113] The bedrock underlying Birmingham was mostly laid down during the Permian and Triassic periods.[110]