Here you go: www.lincswildlife.com/the-sanctuary/charity/
It's about 30 mins from Lincoln, if I remember correctly. They take in unwanted pets - they have literally hundreds of African greys, cockatoos, macaws, galahs etc that either couldn't cope with captivity or where their owners have died/moved. You buy bags of nuts for £1 and they all fly over to the bars and shout to be fed. It's quite something to hear 100 African greys all bellowing, "hello! Hello! Hello!" at you. One or two of them will do it in a funny voice.
Obviously I'd much rather see them in the wild but these are birds that can never live in the wild, so seeing them in big flocks and interacting with each other is miles better than seeing one desultory parrot in a zoo
(not envy).
Then they have a big walk in aviary full of smaller birds - some budgies, some ring necked parakeets (all colours!), some conures etc. These all fly over to you for food. I'd go when it's a bit cold and not school holidays as then there's nobody else there and all the birdies come to you!!
They also have rescue peacocks that follow you around begging noisily for peanuts and I think they've also built a meerkat home.
It's not a big place; only takes an hour or two, but if you combine it with a trip to lovely Lincoln it's quite unique for a parrot lover. And I like spending money on a sanctuary - what would happen to unwanted pets without places like that, as parrots are not easy to rehome!