not really one for geography mate, but if your going into derby with the pit on your left of the (prehistoric) swarkstone causeway then thats where the pit is. Theres a few good uns in there i.e 30+ but its a good old size, have a look on google earth or multimap it to get a better idea.
Theres a silty park style lake in melbourne which may be a better bet. Thye sell a ticket for it in melbourne tackle and guns something like 80 a year days and nights. Not sure where you live but willesley is worth a look to, although it does get busy