The HALS website has a very helpful resource: Hertfordshire Names Online, which includes the Allen Index of pre 1837 Hertfordshire Marriages as well as many other useful resources. This is the direct link:
https://www.hertsdirect.org/ufs/ufsm...d=HALS_INDEXES

Hertfordshire Archives and Local Studies. All Hertfordshire parish records and surviving historical documents are here.
https://www.thegrid.org.uk/learning/hals/

Hertfordshire Registration Districts https://joinermarriageindex.co.uk/pjo...ilRegistration

https://graham.rootsweb.com/herts_exchange/index.html
Herts Look Up Exchange

https://www.hertsfhs.org.uk
Herts Family History Society

https://www.hertfordshire-genealogy.co.uk
Chris Reynolds site which has lots of information about Hertfordshire and useful links.

https://www.hertfordshiremuseums.org.uk
Hertfordshire Museums.

https://www.friends-stjames.org/church_memorials.htm
Monumental Inscriptions; St James the Great, Thorley Herts

https://www.uk-genealogy.org.uk/engla...ons/index.html
The Visitations of Hertfordshire 1572 and 1634

https://bacchronicle.homestead.com/LGChronicle.html
The Leverstock Green Chronicle

https://www.workhouses.org.uk
Hertfordshire Workhouses - Workhouse locations then English Poor law Unions then scroll down to Herts