a large basin at Paddington. This was later linked to the Thames at Limehouse (close to the Limehouse Cut) by the Regent's Canal, completed in 1820. This in turn was linked to the Lea system by the Hertford Union Canal or Hackney Cut (1830). The Regent's Canal had many substantial basins (City Road Basin, Kingsland Basin, Battlebridge Basin, St Pancras Basin, Cumberland Basin etc.), originally lined with industries dependent on traffic from the docks. The City Canal (1805) was built to provide a short-cut across the Isle of Dogs. This was later incorporated into the West India Docks and is no longer connected to the Thames at its upstream end. Other short canals connecting to the Thames included the Grosvenor Canal (1825) and the Kensington Canal (1828). South of the Thames The former Grand Surrey Canal (1807) was intended to run from the Thames at Rotherhithe to the industrial town of Mitcham, but got no further than Camberwell. It closed with the Surrey Commercial Docks in 1970 and has been filled. The Grand Surrey Canal linked to the Croydon Canal (1809) which continued as far as West Croydon; this closed in 1836. Further afield a link from London to Bristol is provided by the Kennet & Avon Canal which connects the Avon at Bath via the River Kennet to the Thames at Reading. Basingstoke could once be reached via the Thames, Wey Navigation and the Basingstoke Canal. The south coast at Littlehampton could be reached via the Thames, Wey and the Wey and Arun Canal. Islands in the Thames Note: Only the largest islands are listed here. A longer list can be found in Islands in the River Thames Chiswick Eyot Eel Pie Island Isle of Dogs Millwall Cubitt Town Topography A list of the highest points can be found in List of highest points in London At the largest scale London lies within the bowl of the London Basin, with most of the built-up area lying on the Tertiary and younger sediments, and only a small part of south London (Sutton, Banstead and Croydon) lying on the chalk backslope of the North Downs. The centre of the basin is dominated by the modern valley of the Thames, which forms a level corridor running from west to east. The modern floodplain is around half a mile wide to the west of Greater London, expanding to two miles wide to the