taken from Martin Lewis's MSE site.
Two x 2for1 at Alton Towers & more
Newspaper based offer
Pick up the Mirror newspaper (45p) on any day from Saturday 9 Wednesday 13 May and youll find two 2for1 vouchers valid at Alton Towers Resort, Chessington World of Adventures, Thorpe Park, Legoland Windsor, Warwick Castle, Madame Tussauds, The Dungeons and Sea Life Centres/Sanctuaries (excluding the Sea Life London Aquarium).
There are currently a few different theme park vouchers, but this is a particularly strong deal as you get two vouchers, both valid at the major theme parks, for just 45p. The vouchers are valid until Sunday 26 July at Thorpe Park and Friday 31 July at all other attractions.
Each voucher is valid on the day only, allowing one free entry when you buy a full price adult ticket at the ticket booth. Although some theme parks offer a discount on online tickets, you can make a good saving using this voucher on the day.
For example, bought online, two adult tickets for Alton Towers cost £58 (£29 each); use the voucher and youll only pay £36 for both of you (the on-the-day price for one adult), saving you £22. There are some exclusion dates, so make sure you check these in the terms and conditions on the voucher before you go.
You cant use the vouchers with other offers or online / advance tickets, and you can only use one voucher per transaction. Although the Mirror have confirmed theyre planning to print both vouchers each day, theres a chance that only one may be printed due to space constraints, so its worth checking in the paper before you buy.