Swanscombe is a town in the Borough of Dartford in Kent, England. It lies east of Dartford and also north-west of Gravesend, in the civil parish of Swanscombe and Greenhithe. At the 2001 UK census, the Swanscombe selecting ward had a population of 6,418. Swanscombe was important in the early history of cement. The initial cement manufacturing works near Swanscombe were opened at Northfleet by James Parker, around 1792, making "Roman cement" from cement rock brought from the Isle of Sheppey. James Frost opened up an operate at Swanscombe in 1825, using chalk from Galley Hill, having patented a new concrete called British Cement. The Swanscombe plant was consequently acquired by John Bazley White & Co, which ended up being the largest element of Blue Circle Industries when it created in 1900. It finally shut down in 1990. Between 1840 and 1930 it was the biggest cement plant in Britain. By 1882 several cement producers were operating throughout the north Kent area, yet the resulting dirt pollution drove individuals of Swanscombe to take legal action versus the neighborhood concrete jobs. Regardless of numerous technological technologies, the trouble persisted into the 1950s, with telegraph lines over an inch thick in white dust. Modern cement kilns in Kent utilizing smokeshafts 170 m (550 feet) in height are now claimed to be the cleanest worldwide. Nonetheless, the adjoining Medway communities are reported to be one of the most polluted populated area in the UK, and the cement market adds to acid rain in Scandinavia.