A few years ago, I set off with three friends to walk the length of the Los Angeles River, a largely parched 82-kilometre deep-walled concrete channel stretching from Canoga Park to Long Beach. Entry into the river is forbidden, and each of us revelled in the adrenaline rush of hopping over the fence in the predawn hours to begin the three-day journey.
Once inside the channel, we entered our own world, walking straight through the centre of the city but eerily divorced from it. Others were there too. We encountered homeless people living in tent communities, dog walkers, cyclists, groups of kids dancing to hip-hop and artists reclaiming slices of neglected land. In other words, the river was being remade into public space by wilful acts of trespass.