Brennand Farm is often claimed to be the true centre of Great Britain. This is about seven kilometres north-west of Dunsop Bridge - which has the nearest BT phone box to the 'true centre'. A plaque reads “You are calling from the BT payphone that marks the centre of Great Britain”. The location was calculated by Ordnance Survey as the centroid of the two-dimensional shape of Great Britain, including all its islands.Haltwhistle claims to be the centre by a different method.