This map is part of the Ordnance Survey series of maps of England and Wales at a scale of 25 inches to the mile.
The map was revised in 1896 and published in 1898.
The sheet in question covers the complete old town of Harwich with the railway running down to Lower Dovercourt as far west as the “Grapevine” and the site of the modern Vines Estate and out to the east to the extent of the Stone Pier.
Map detail on the Harwich History Wiki is reproduced with the permission of the National Library of Scotland and this map can be accessed at their site.