Headed out for a wander beside the Lea in the late afternoon sun. They’re building a whole new world over the road – the pace of building of the Olympic Park is startling. We duck down away from the madness and into the quiet shade of the willow trees.

On a section of the bank that looks prone to flooding the boys spot a dead hairy crab washed up with piles of rubbish. The eldest suggests that the pollution must have killed it and he then returns the decaying crustacean to the water.

We pass through dense thickets of pink flowers catching the sun. Using my 1950’s wildflower book I posit that these may be Himalayan Balsam, that this tattered tome tells me are commonly found by rivers and streams.

The boys can’t resist the pull of the open sea of pitches on Hackney Marshes and they sprint across. We follow the water again along the Hackney Cut past the barges, joggers and fishermen and reach Lea Bridge Road at the magic hour of last light.