The Abbey-row cholera outbreak took place in September 1857 in West Ham by the eastern branch of the Lea River, north of the Isle of Dogs.  The location is shown as a red box in the right side of the 1841 map.  For a more detailed view of the outbreak location, as shown in an 1862 map, click here.

Source: Davies, Benjamin Rees. Map of London, 1841 in Barker F and Jackson P. The History of London Maps, Barrie and Jenkins, London, 1990.