to the north around Farlow. Overlying this is the Cornbrook Sandstone formation, the local representative of the Millstone Grit underlying the ground between Cleehill village and Knowle and also to the northeast of the hill. This is succeeded by the mudstones, siltstones and sandstones of the Lower and Middle Coal Measures which makes up much of the rest of the surface of the hill extending southwest to Knowbury and northeast beneath Catherton Common. It contains seatearths and coal seams which have been worked in the past. The lowermost and most extensive of these, just above the basal sandstone of the Coal Measures is known as the 'Gutter Coal'. The dark coloured dolerite of the sill is known locally as Dhu Stone ('dhu' may have arisen from the Welsh 'du' meaning 'black'). It is an olivine basalt which appears to have been intruded as a sill between sandstone layers within the unconsolidated strata of the Middle Westphalian sediments soon after deposition of the latter. A fault system runs ENE-WSW across the southern flanks of these hills. The northerly downthrowing Leinthall Earls Fault runs off to the WSW whilst the Titterstone Clee Fault runs off the ENE. Other smaller faults, some at right angles to these named faults, affect both the sedimentary strata dn the intruded sills. Near the summit is the Giant's Chair – a pile of boulders created during cold phases of the Devensian ice age. History, quarrying and land usage Near the summit trig point are the remains of a Bronze Age cairn, dating back up to 4,000 years and indicating that the summit was a likely ceremonial site. Although partly destroyed by quarrying, Titterstone Clee's Iron Age hill fort or encampment, enclosed by a huge boundary earthworks, has fared better than those on Brown Clee. It is of note that the walls of the fort are made up of stone blocks, instead of earth banks. Clee Hill is one of only a few hills and mountains noted on the Hereford Mappa Mundi, a 13th-century map of the world displayed at Hereford Cathedral. In medieval times ironstone and, later, coal were mined, in particular from bell pits: localised mine shafts, one of which has now flooded to form a lake. Over the years large numbers of quarries were opened up on Titterstone Clee to exploit the dolerite. All but one, on Clee Hill, are now abandoned. The largest quarries