Here are the details of maps for Chatham:
This very busy and detailed map covers an area from Eastgate House in Rochester eastward to part of the Royal Naval Hospital in Gillingham. It therefore covers most of Chatham town and also part of Rochester (though not as far west as the cathedral). Features include High Street, Eastgate; Chatham, Rochester, Chatham Central stations; New Road, New Avenue, Church Hill, Brook, Royal Marine Barracks, Chatham Barracks, Garrison church, Town Hall Gardens, Southill Barracks, Ordnance Terrace (once home to Dickens), Chatham Hill, Ordnance Place, Pattens Lane, tramways, Troy Town, Chatham Intra, Chatham Ness, Sun Pier, numerous wharves and piers alomng the Medway. A few sites are left blank for security reasons (eg Fort Amherst) but there is bags of interest on the map. Dickens referred to Chatham as Dullborough; this map is anything but!
You might find this index map useful.