"TREGARE, a parish in the lower division of Ragland hundred, county Monmouth, 6 miles S.W. of Monmouth, its post town, and 2 from Ragland. The living is a curacy annexed to the vicarage of Dingestow, in the diocese of Llandaff. The church is old. The parochial charities produce about £24 per annum."
[Description(s) from The National Gazetteer of Great Britain and Ireland (1868)
Church and chapel data from The Religious census of 1851 : A Calendar of the returns relating to Wales, Vol 1, South Wales. Ed. by I.G Jones, & D. Williams. UWP, Cardiff, 1976. The names given towards the end of each entry are those of the informants. Check with Gwent RO to see what extant records are held, and possible names of chapels/churches built after 1851.
Tregare Parish; Statistics; Area 2387 acres; Population 166 males, 159 females, total 325
Tregare Parish Church Attendance - evening 66 1 service in English Thomas Morgan, Vicar, Dingestow Vicarage
Family Search have an interactive map called "England and Wales Jurisdictions 1851" showing parish (and other) boundaries with optional background maps such as Ordnance Survey. There is also a Search facility, do read the guidance notes to get maximum benefit from this useful resource. See here for further background information to assist in the interpretation of this data
Kain, R.J.P., Oliver, R.R., Historic Parishes of England and Wales: an Electronic Map of Boundaries before 1850 with a Gazetteer and Metadata [computer file]. Colchester, Essex: History Data Service, UK Data Archive [distributor], 17 May 2001. SN: 4348. Here is a gazetteer/finding aid plus a set of overview maps to accurately identify the position of parishes within the county.
You can see maps centred on OS grid reference SO417102 (Lat/Lon: 51.787405, -2.846615), Tre'r-Gaer / Tregare which are provided by: