Temperatures are soaring around Britain, and Britain's outdoor pools are expecting record numbers of visitors this weekend as holidaymakers and locals desperately try to cool off.
Want to know where to go? Here are four suggestions for starters:
Bude Sea Pool, Cornwall
Bude Sea Pool in North Cornwall is a rare construction: a semi-natural pool created underneath the curve of the cliffs that floods twice a day with cool sea water from the Atlantic Ocean at high tide.
The pool was created in the 1930s to provide a safe haven for swimmers wanting to experience wild, open water swimming without the risk factor and it's still popular with locals and tourists today.
Admission is completely free.
The beautifully restored Tinside Lido in the costal town of Plymouth, Devon features art deco gems - like the central fountain: it almost feels as though you're swimming on the prow of a ship with its semi-circular shape and panoramic view out to the ocean.
The salt water pool has a sunbathing terrace with loungers and deck chairs. Prices start from £2.80 for children under 15 and £3.90 for adults with concessions priced at £2.90. A family swim session costs £11.30 or a family season ticket, valid until September 2013, is £100.
This south London summer oasis is a city swimming institution. With its colour blocked, pantone changing huts, the Lido has been welcoming London residents and visitors since 1906.
At just shy of 90m, it's the UK's largest outdoor freshwater pool.
To swim at Tooting Bec Lido you need to be a member of the South London Swimming Club, which is based at the Lido. Annual SLSC membership is £125.
Stonehaven Open Air Swimming Pool
Britain's most northerly outdoor pool, Stonehaven Open Air Pool is Scotland's only Olympic length heated salt water lido. The setting is glorious: this is where the Highlands meet the North Sea, with the cliffs to the north and south and the wide sweep of the bay to the east.
Every Wednesday during the summer, you can swim under the stars as the pool opens up for midnight swims, and there are swimming sessions for all tastes, including quiet swims for adults, early morning sessions as well as kids fun periods and competitions.
In the mood for something different? Check out our gallery of the weird swimming pools around the world below!
In pictures: the world's weirdest swimming pools
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