Winning tip: Billingsgate fish market
Whether you are in east London to visit the Olympic Park or just looking for a way to keep the kids occupied, head down to Billingsgate and take a picnic, but be sure to pack a mackerel (as the fish market closes at 8.30am). When you spot Sammy the seal (although most likely Simone, in my opinion) in the Thames near the market throw the fish to him/her. He/she has been hanging around here for a few years and why not, with all that fish around? You might even get to see a porpoise too.
Billingsgate market, E14, open Tues-Sat 5am-8.30am
It's worth making a trip to find Hampton's open-air lido, as the Canadian triathlon team will be doing for their training in the coming week. This little gem, saved from demolition in 1985, is hidden away in south-west London, in woodland on the outskirts of Bushy Park. Open 365 days a year, it has a heated 36m pool, plus a learner pool and a grassy area to spread rugs out beneath shady trees. The building along one side has a gym and fitness studio. Upstairs is the small Sun Deck cafe for breakfast (best porridge in London), lunch, drinks and snacks, and a south-facing terrace overlooking the pools. There are music concerts on the grass in the summer and if you join the Poolside Club you can swim and barbecue in the evenings outside public opening hours.
High Street, TW12, 020-8255 1116, hamptonpool.co.uk, adults from ?4.70, children aged four-15 from ?2.95, under-fours free. Open 9am-9pm with various sessions, check website for details
Rock climbing is one of the fastest-growing sports in London, and the capital's indoor centres are now overflowing in peak hours. London has a new, easily reached outdoor boulder park five minutes from Fairlop tube stop on the Central Line, and close to the main lake at Fairlop Waters. It's suitable for all climbers from beginners through to advanced, and offers them a rare opportunity to climb outdoors. Crucially, this is a boulder park so ropes are not a prerequisite (although you can use a top rope on the larger boulders) – a big bonus for newer climbers.
Forest Road, IG6, 020-8500 9911, tinyurl.com/fairlopwaters, free admission
These are three life-guarded, open-air swimming ponds (yes, real ponds, weeds and all!) in the heart of London. Each pond (ladies', men's and mixed) has its own atmosphere, whether you want secluded bathing among ducks and lily pads, clear open water for training, or a place to splash about with friends and wash away the London grime. At each pond there is a grassy bank for sitting, a jetty to dive off and changing rooms with showers. Swimming in one of the ponds is the most serene yet invigorating way to finish off a summer's day in the capital. Oh, and did I mention that they're open all year round?
020-7485 3873, tinyurl.com/hampsteadswim, adults ?2, children ?1. Mixed pond open 7am-6.30pm (times change 24 Sept), opening times vary for men's and ladies' ponds, but details are displayed at the ponds themselves
The Secret Cinema is one of the most innovative projects in London. The crew rents a discreet venue in the city and constructs an interactive version of the film, which they show at the end of the evening. The audience are expected to dress up and immerse themselves in the environment, heightening the eventual experience of the film itself.
secretcinema.org, tickets ?27.50