The Roman Map of Britain Ciano ? Penzance?

Giano (R&C 1next

    Being the first of the civitates listed, Giano presents some interesting difficulties. Margary's Roman road 492 [M492a Exeter - North Tawton - Okehampton - Launceston and M492b Launceston - Bodmin - Redruth] runs down the spine of the Cornish peninsula. The modern A30 now represents its general course. Margary makes no further suggestion of its course west of Redruth, but the entries following Giano seem to indicate that it visited two sites on the river Hayle - Eltabo and Elconio. And, consistent with the general path of A30, a fair presumption can be made that M492 continued on to Mounts Bay in the vicinity of Penzance SW4630.
    At first glance the Cosmography's form appears to be a scribal assimilation to It giano 'covered gallery' (L ianus 'a covered passage'). From 'A Topographical Dictionary of Ancient Rome': Ianus - an arch or gate, intended for a passage way. It could be that Giano updates Iano to a more modern form, either by the original author or the Ravennan scribe. If so, the 'covered passage or gallery' might represent a feature of the coast named by Latin-speaking tin-traders. South of Penzance, further down the coast, is the port at Mousehole SW4626, a site of early tin trading. It has a small offshore island known as St Clement's Isle or Mousehole Island, far less prominent than St Michael's Mount opposite Marazion. Mousehole does have one seaward feature, that if not the source of its name, would still be of note to a mariner. A few hundred yards south of the town is a cave in the sea-cliffs that is fifty feet tall and thirty feet wide at its entrance.
    The manuscript offers what may be another Iano at R&C 201, the first site listed after the forts of the Antonine wall.

    Alternatively, if Giano represented a transcriptional error for Ciano, Old Irish cían or chían 'long' might serve as a name of the river at Chyandour SW4731. While not particularly lengthy (a relative term), it could be considered long-enduring, a constant source of water. Perhaps Ciano relates to the river-name Chew (see ERN p. 77 W. cyw 'young of an animal') This coastal place-name next Penzance is regularly translated 'house/cottage on the river'. Chyandour Chiendour 1452.

    Another possibility, the name might be the same as W. ci 'hound, dog', diminutive ci-an.

NTSMR-NA78 Foage Farm; Zennor; Penwith - Romano-British field system SW466275

*A Topographical Dictionary of Ancient Rome. Samuel Ball Platner. Thomas Ashby. London: Humphrey Milford. Oxford University Press. 1929

LESCUDJACK CASTLE; PENZANCE; PENWITH; CORNWALL; Damaged earthwork remains of an Iron Age univallate hillfort or Iron Age/Romano-British round. SW 4753 3102 NMR_NATINV-423950.