Got back yesterday from a 4 day break at Butlins with the family and inlaws. My parents took us there when I was a lad (about 35 years ago) and it's changed a lot since then. In their hayday holiday parks like Butlins and Pontins were really popular but as package holidays and overseas travel became more popular their usage declined and many of the parks were closed. There are now only 3 Butlin's parks left in the UK now but there used to be 10. Here's the the Butlins Wikipedia page for those who want some more info on the history.
It cost £500 for a 5 day/4 night stay in a Gold apartment which slept 6 people (room to sleep 8) which included buffet style all you can eat breakfast and dinner each day. The food wasn't too bad but I wouldn't have wanted to eat if for much more than the time we were there.
Entertainment wise there is plenty to do with entertainment and activities organised for kids throughout the day and shows in the evening which cater for adults and children. Most of the shows are put on by the same entertainment team consisting of a mix of singers and dancers and they were pretty good to be honest.
One of the main things Butlins is known for is its "Redcoats" who are the face of the holiday park and can be found all over the place interacting with the children and offering help and advise to adults. They wear red jackets so they are easily distinguished and they remind me of the jolly people you find in American theme parks like Disney.
We spent most of our time in the Skyline Pavillion which is a large covered area containing food courts, entertainment stages and lots and lots of arcade machines. You put money into the machines but instead of winning money you get tickets which you save up to exchange at the end of the holiday for prizes which are worth about a tenth of the cost you paid for the tickets. We ended up saving up 16,000 tickets which bought us a wireless speaker and some plastic crappy toys. I don't even want to think about how much we spent to win the tickets but it would have been well over £100. We had fun thought and made some good memories and got to spend some quality time with the family which is priceless.
There is alreay talk about us going back next year.