My little sister and I had a game when we were kids. Our house had more furniture than space. The lounge had bookcases, occasional tables, a sideboard, sofas, chairs. The game was to get around the room without touching the floor. For the floor was lava. We’d climb from table to bookcase, jump on to the sofa, leap from there to a chair. The general aim was to follow the wall perimeter but diversions were encouraged to climb over something more interesting. When we moved to a larger house dabs on the floor had to be permitted, for we had to work with what we had.
And that’s the basis for Gnarbital. The room is London, the perimeter its M25 orbital motorway. Main roads are the floor, bridleways the bookcases, byways the tables, tow paths the sofa and lanes the chairs. This time it’s a soft perimeter though, and we’ll cross the motorway more than 30 times on our way round. The aim is to stay close to its path but taking the most interesting route. So using a bridleway over a road, even if the road is more direct or tracks closer. Because it’s not about how quickly we can get around but how much fun we can have on the way.