Abbey Well water have extended their "free swim with a bottle top" offer from Monday only to Monday - Friday.
Tesco sell it for 70p a bottle but I am sure you can find it cheaper elsewhere.
The offer seems to be on for a year.
From the website : What is the 'Schweppes Abbey Well' SCHWIM FREE activity?
'Schweppes Abbey Well' are offering a free swim to anyone who buys a bottle of 750ml still sportscap or 500ml still or sparkling water.
Take the 'Sch...wim cap' bottle top to your nearest participating pool to take part.
to find your nearest participating pool.
My local has a sauna, steam room and jacuzzi - so a pretty decent deal.
Couldn't see it posed already, please delete if duplicate.