Parish Maps, etc., in 1851 - an essential resource

Try the 

online parish maps 

on familysearch. 

They are hidden under the title England Jurisdictions 1851 and provide a google-based map of the country showing the parish and county boundaries. In addition you can click on a parish and get useful information. For instance for Hatfield it tells you:

Bishop's Hatfield is an Ancient Parish and a market town in the county of Hertfordshire. Totteridge is a chapelry of Bishop's Hatfield
Other places in the parish include: Woodside, Newgate Street and Roe Green
Parish records begin 1653, Bishop's transcripts 1603
Non-Church of England denominations identified in Bishop's Hatfield include Baptist, Independent / Congregational, Primitive Methodist and Wesleyan Methodist

Parish		Bishop's Hatfield		For each of the jurisictions it is possible to get an appropriate map
County		Hertfordshire
Civil Registration District		Hatfield
Probate Court		Court of the Archdeaconry of Huntingdon (Hitchin Division)
Diocese		Post 1844 - Rochester, Pre 1845 -Lincoln
Rural Deanery		Hertford
Poor Law Union		Hatfield
:Hundred		Broadwater
Province		Canterbury

In addition you can get details of contiguous parishes - or those within a given distance.