Northumberland role in the Industrial Revolution from the 18th century on. Many coal mines operated in Northumberland until the widespread closures in the 1970s and 1980s. Collieries operated at Ashington, Bedlington, Blyth, Choppington, Netherton, Ellington and Pegswood. The region's coalfields fuelled industrial expansion in other areas of Britain, and the need to transport the coal from the collieries to the Tyne led to the development of the first railways. Shipbuilding and armaments manufacture were other important industries before the deindustrialisation of the 1980s. Northumberland remains largely rural, and is the least-densely populated county in England. In recent years the county has
Hudson County, New Jersey densities in the United States the Hudson communities have remain fragmented, due in part to New Jersey's long history of home rule in local government; geographical factors such as Hudson River inlets/canals, the cliffs of the New Jersey Palisades and rail lines; and ethnic/demographic differences in the population. As the county sees more development this traditional perception is challenged. Hudson County is the most densely populated county in New Jersey and one of the most densely populated counties in the United States, at 14,974 residents per square mile (5,781/km²). The only city in Hudson County among the 100 most populous