Anglo-Welsh Basin. Carboniferous intrusive rocks A series of dolerite and basalt intrusions occur within the Carboniferous sequence including the Brewin's Bridge microgabbro dyke, London Fields basalt sill and Rowley Regis microgabbro lopolith. Associated with these is a basaltic vent at Barrow Hill. Geography The Geopark has been established across the entirety of the boroughs of Dudley, Sandwell, Walsall and Wolverhampton. As such it encompasses a wider area than the traditional Black Country, though the boundaries of this distinctive historic urban landscape within the West Midlands are difficult to pin down firmly. Originally more than a hundred individual villages, the area was at the heart of the Industrial Revolution of the eighteenth century. The name is said to derive from the blackened and scarred landscape which resulted from the intensive exploitation of its natural mineral wealth. The area overlaps the South Staffordshire coalfield. Turner's Hill near the heart of the area reaches to 271m above sea level whilst the landscape rises to the 227m high viewpoint of Barr Beacon east of Walsall and, on its southern boundary, to a height of 224m at Wychbury Hill, a northern outlier of the Clent Hills. The area drains to the River Stour to the west, the Penk to the north and eventually to the Tame to the east via numerous tributaries. It is criss-crossed by canals including the Tame Valley Canal, Rushall Canal, Wyrley and Essington Canal, Dudley Canal, Stourbridge Canal, Birmingham Canal, Shropshire Union Canal and Staffordshire and Worcestershire Canal. Notable features In 1956 Wren's Nest National Nature Reserve (NNR) became the first area in England to be designated as a national nature reserve for the geological interest of its bedrock, and remains a key ‘geosite’ within the modern Geopark. There are a further 16 SSSIs within the Geopark and 105 SINCs. The Dudley Canal and Tunnel Trust provides underground canal tours and a visitor centre. Castle Hill and Zoological gardens is a site of geological and cultural interest. Dudley Castle of motte and bailey construction dates back to the 11th century. See also UNESCO Global Geoparks List of National Geoparks Sustainable tourism References External links 2020 establishments in England Geology of England Geoparks in England Global Geoparks Network members West Midlands (county) UNESCO