In 1887, John Bartholomew's Gazetteer of the British Isles described Plymouth like this:
Plymouth, parl. and mun. bor., seaport, and naval station, Devon, on Plymouth Sound, between the estuaries of the Plym and Tamar, 53 miles SW. of Exeter by rail - mun. bor., 1395 ac., pop. 73,794; parl. bor., 2061 ac., pop. 76,080; 7 Banks, 4 newspapers. Market-days, Monday, Thursday, and Saturday. ...
Plymouth, in the larger sense, consists of the " Three Towns " of Devon-port, Stonehouse, and Plymouth, the two first forming the borough of Devonport (which see). Plymouth proper is built upon 2 eminences and the hollow between them. The southern eminence is called The Hoe, and is laid out as a promenade and recreation grounds. The market place covers nearly 3 acres. The mfrs. include sailcloth, brushes, rope and twine, earthenware, &C. There are shipbuilding yards, foundries, sugar re-fineries, starch works, breweries, flour mills, flax mills, and limestone quarries. The fisheries are very productive. Steamers sail regularly for North America, the Cape, Australia, and New Zealand. The accommodation for merchant vessels includes Button Pool and Mill Bay, at the last of which extensive wet docks have been constructed. (For shipping statistics, see Appendix.) As a naval station Plymouth is second only to Portsmouth, the spaciousness of the Sound affording anchorage to a large number of ships. The breakwater, constructed at a cost of £2,000,000, is nearly a mile in length. At its W. extremity is Plymouth Lighthouse, 76 ft. high, with occulting light 63 ft. above high water and seen 9 miles. Plymouth was called Tamarworth by the Saxons, and Sudtone (i.e., South Town) by the Normans, and was a mere fishing hamlet until after the reign of Henry II., when its natural advantages as a seaport and naval station were perceived, and the town rapidly rose in importance. In 1346 it sent 26 ships and 600 men to the siege of Calais, and its contribution to the fleet on the threatened invasion by the Spanish Armada was second only to that of London. The name of Plymouth was taken in 1439, when it received its charter from Henry VI., since which period Plymouth has regularly returned 2 members to Parliament.
GB Historical GIS / University of Portsmouth, History of Plymouth in Devon | Map and description, A Vision of Britain through Time.
Date accessed: 29th March 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 " Plymouth ".