If you have English ancestry, especially if your ancestral families were in England before 1851, then you need to know about the FamilySearch site titled English Jurisdictions 1851.
At this site, you can see the boundaries of every English parish, plus much more information. For example, I put the name of "Hilperton" in the search field and saw:
Hilperton is a parish in the county of Wiltshire. Zooming in on Hilperton, I can see the outline of the parish, the neighboring parishes, and an information box:
This information box tells me that Parish Registers for Hilperton started in 1694, and that there are Bishop's Transcripts from 1622. That is really useful information for a researcher. The box also tells me that there were non-Church of England in Hilperton for the Particular Baptist and Wesleyan Methodist churches, but it doesn't provide any years that they were active.
Clicking on the "Jurisdictions" tab shows me:
The Jurisdictions listed include:
* Place: Hilperton
* County: Wiltshire
* Civil Registration District: Melksham
* Probate Court: Court of the Archdeaconry of Sudbury
* Diocese: Salisbury
* Rural Deanery: Potterne
* Poor Law Union: Melksham
* Hundred: Melksham
* Province: Canterbury
Each item on that list may lead to genealogical records if the researcher knows the definitions of the terms and the records that may be found in the appropriate repositories.
The third tab is for "Options":
The Options offered are:
* List contiguous parishes
* Radius search (provides list of parishes within N miles - your choice!)
* Search the Family History Library Catalog
* Search the Family History Research Wiki
* Remove selection
I chose the Family History Library Catalog, and received:
By following the link for Hilperton, I can see what records are available on the shelf at the Family History Library in Salt Lake City and the microfilms that are available for rent at a local Family History Center.
There are two tabs on the left side of the screen - all of the above was performed using the "Search" tab. I clicked on the "Layers" tab and selected all of the boxes in order to superimpose all of the jurisdictional Layers on the map:
The different jurisdictions are outlined and labeled in different colors. This map uses the "EJ1851" base map (as shown in the lower left-hand corner). To see a Google street map of the area, I selected "Google Street Map" in the Base Map area, and saw:
This is a pretty cool scheme to see English Jurisdictions in 1851. Using this site, I can see what records are available, which parishes are nearby, and how to get there in the modern day.