London Aquatics Centre｜Olympic pool

Student noteZaha Hadid-designed 2012 Olympic venue, now open to the public: the 50m main pool, diving pool and warm-up pool are all swimmable, single-entry tickets are very cheap, lockers take coins, and there's a gym inside too. It's in the Olympic Park, worth a walk round the park after your swim; check the lane availability timetable online before peak hours.