In 1887, John Bartholomew's Gazetteer of the British Isles described Upnor like this:
Upnor, eccl. dist., Frindsbury par., Kent, on river Medway, on NE. side of Strood, and opposite Rochester, pop. 728; P.O. Upnor Castle, built by Queen Elizabeth for the defence of the Medway, beat off the Dutch fleet in 1677; it is now used as a powder magazine.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing Upnor has changed, please see our redistricted information for the modern district of Medway. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Upnor and units named after it.
GB Historical GIS / University of Portsmouth, History of Upnor, in Medway and Kent | Map and description, A Vision of Britain through Time.
Date accessed: 24th February 2017
Click here for more detailed advice on finding places within A Vision of Britain through Time, and maybe some references to other places called "Upnor".