"LLANGSTONE, a parish in the lower division of the hundred of Caldicott, county Monmouth, 4 miles N.E. of Newport, its post town. It includes the hamlet of Llanbeder. It is a small agricultural parish. The living is a rectory in the diocese of Llandaff, value £153." [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 established after 1851.
Llangstone Parish; Statistics; Area 1314 acres; Population 124 males, 109 females, total 233
Langstone Parish Church Attendance - morning 50 + 10 scholars 1 service inn English Thomas Williams, Minister
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 ST370898 (Lat/Lon: 51.603498, -2.911054), Langstone which are provided by: