The positive influence of Waterlog (1999) by Roger Deakin (1943-2006), continues to grow. As summer finally appears here and opportunities for 'wild' swimming (aka outdoor swimming) present themselves, his messages about freedom of access to clean rivers, pools, seas and lakes resonate more than ever at a time of water quality scandals. Deakin also reminds us of the joys of lidos, mostly built in the 1930s, many of which have survived or been rescued by local groups, so this week we have five of Britain's amazing lidos. This is London Fields Lido (1932), a 50m heated pool, open all year round, and beloved of the people of Hackney.