Went to Walsingham a couple of years ago and it is probably the best. Fair distance for us and its a rotten place for parking.If you're in East Anglia there are plenty of places for snowdrops. Walsingham Abbey in North Norfolk is one of the most popular ones. But they are out everywhere at the moment.
I've not done an actual trip out specifically for snowdrops but I've caught some in a few local spots.
I keep an eye on the local facebook groups because someone always posts when snowdrops/bluebells are out. The trick with both is to get them at the peak before they start deteriorating.