Ridlington is a small village in North Norfolk and after I had a little visit to their church, this is what The Concise Oxford Dictionary Of English Placenames say about the origins of the name.
Ridlington, Norfolk. Ridlinketuna in Domesday Book, Redlington in 1199 and Ridelington in 1254. May be derived from a person, Hrethel.
I’m not sure who this person might be, but it’s the settlement or enclosure of Hrethel and his people. It’s not the most descriptive of place names, I like the ones which say they’re up a hill or something, but it’s an old English name that has stuck relatively unchanged for nearly 1,000 years.