Every once in a while I discover a truly wonderful, utterly walkable neighborhood. Sometimes it requires traveling 4,000 miles to find it. On my recent trip to London I stayed in a neighborhood in the borough of Hackney, just north and east of the City. I checked in to my Air B&B and set off on foot to explore. I was immediately captivated and happy. Don’t get me wrong, you could set me down on any street there, and I’d take one look at the color of the bricks and the distinct chimneys and I’d exclaim “I’m in London, and…