A town which is located somewhere in the North of England and has Blackbury as a close neighbour - both are served by the same local newspaper, the soaraway Blackbury Evening Post and Gazette. Grimethorpe, Blackbury and Newtown may all be part of the same conurbation - ie, three formerly separate towns which, like inkblots on filter paper, have spread out to overlap each other.
Johnny Maxwell and his family and friends live in this general area. There must be something in the air locally, as it is also remarkable for the presence of Mrs. Tachyon the very strange bag lady, and - were they to have sought fame, which they didn't - the Nome population hiding under the floorboards of Arnold Bros (est. 1905), a long-established local department store, which to them is a Paradise graciously conferred by the Gods. Until they have to leave it, that is...
There is actually a Roundworld Grimethorpe, but it is located in South Yorkshire between Barnsley and Wakefield, on the far side of the Pennines from the conurbation of Greater Manchester, where (supposedly) the fictional Grimethorpe is based. It is a former colliery village, which has a brass band, formed in 1917 to provide a leisure activity for miners, and the band is notable for being the first brass band to play at the Proms. The 1996 film Brassed Off is a dramatised account of the trials and tribulations of its members following the systematic destruction of the mining industry in the 1980s, and the consequent mass unemployment which blighted a multitude of small colliery towns across Yorkshire, Nottinghamshire and Derbyshire.