UK retailer WHSmith is offering a free booklet containing six 2 for 1 theme park vouchers with any purchase from March 8. The vouchers are valid at Alton Towers, Chessington World of Adventures, Thorpe Park, and Legoland Windsor along with a number of other UK attractions operated by Merlin Entertainments Group.

To get the vouchers, all customers need to do is buy anything from a WHSmith high street store between March 8-21 or April 5-11, 2010. There is no minimum spend, so even those buying a newspaper or some chewing gum for a few pence will get the vouchers. The vouchers will also be available through WHSmith travel stores between March 15 and April 11.

The vouchers can be used when buying a full price adult ticket on the day (at the higher gate prices rather than discounted online tickets). A single adult ticket bought on the gate costs £38 at Alton Towers. With two online adult tickets costing £60.80, there is a potential saving of over £22 from taking advantage of the offer.

The vouchers are valid through most of the 2010 season, but there are some block-out dates on which they can't be used:

• Alton Towers - Valid until October 31, 2010. Block-out dates: June 27, 2010.
• Thorpe Park - Valid until November 7, 2010. Block-out dates: October 23-31, 2010.
• Chessington World of Adventures - Valid until November 1, 2010. Block-out dates: all Zoo Days
• Legoland Windsor - Valid until November 7, 2010. Block-out dates: None (note that the park is closed on some days during the season).

As well as the four theme parks, other major attractions included in the offer are Madame Tussauds, Warwick Castle, The Dungeons, and Sea-Life Centres and Sea-Life Sanctuaries across the country.