Lanarkshire occupies the valley of the river Clyde, which crosses the county from the north-west to south-east. It is predominantly flat and agricultural, rising to the south with the Lowther Hills of the Southern Uplands, with Culter Fell on the border with Peeblesshire being the highest point at 748 m (2,454 ft). In the east a small portion of the Pentland Hills lie in the county, in the vicinity of Tarbrax and Dunsyre. In the far south lies the Daer Reservoir. Northern Lanarkshire is dominated by the Glasgow conurbation, Scotland's largest city, though some small bodies of water can be found such as the Roughrigg Reservoir, Lilly Loch, Hillend Reservoir, Forrestburn Reservoir and Black Loch.