There are quite a few sources of old maps of Hexham in books and online, which I list below. You could certainly use the ones on the Hexham Historian website photo archive for educational purposes – there are some very useful ones there : hexhamhistorian.org in the Historic Hexham section – but I couldn’t say what would be permitted in the way of reproduction with any of the others. There are quite a few aerial photographs in the Town Views section of the Hexham Historian photographs section, too.
The oldest plan of the town is from 1826 : A Plan of Hexham from Actual Survey, John Wood, 1826; online at https://communities.northumberland.gov.uk/Hexham_C15.htm. Northumberland Archives at Woodhorn have a copy of this.
The next one is the Tithe Redemption Plan : Tithe Redemption Plan of Hexham Township, 1839. Online at https://communities.northumberland.gov.uk/Hexham_C15.htm . Again, there is a copy at Northumberland Archives.
Just before the Ordnance Survey started up, another plan of Hexham was published in connection with an investigation by the General Board of Health into sanitary conditions in Hexham : Town of Hexham, showing the present state of the drainage, lighting, water supply, etc, Plan accompanying Robert Rawlinson’s Report to the General Board of Health, 1853, reproduced in Dirty Old Town, Hexham Local History Society, 2015.
The first Ordnance Survey map for Hexham dates from about 1860, and there are new editions at frequent intervals after that up to the present date. All the OS maps up to the 1950s, at scales from 1:2500 upwards, are available online on the fantastic National Library of Scotland website : https://maps.nls.uk/
While there is no known surveyed plan or map of Hexham from before about 1800, the local historian Tom Corfe did an excellent reconstruction of what the town was like in medieval times, based on written historical sources. It is in his book Hexham Heritage (2nd Edition) – there are copies in the library.
I hope this helps.
