Agree with Cupcake that Norfolk is gorgeus. We've just been staying in Happisburgh and spent a couple of days at Sea Palling (between Yarmouth & Cromer). Sea P has a caravan site that is about 300 yards from a great sandy beach and between the site & the beach there is a fantastic kids' playground & a pub that does food.
There's not much of a town there but depends what you want. If your kids are small and you want a quiet easy holiday it's great. If you want more entertainment close at hand, pehaps not.
PS - Nearby things to do include steam trains, boat trips, farm parks & Norwich is about 20 miles.