There's a good series on BBC 2 at the moment about London, presented by Peter Ackroyd. In the first part, he looked at the effect of fire on London over the centuries. It's surprising — given how often London has been totally devastated by fire — that the lines of the old, winding streets seem to manage to re-assert themselves, as if the city is a living thing, and re-grows its old form to heal the wounds. Christopher Wren was frustrated by the conservatism of Londoners, as his grand plans for piazzas and broad avenues surrounding St Paul's were scuppered by everyone wanting to build their new homes and businesses on the smoldering foundations of the old. Even the brutal, rigid lines of the new offices around St Paul's — built to replace buildings bombed in The Blitz — are now being replaced by a scheme which follows the lines of the old City.
I see this as a good thing. Gridded street plans are very efficient and easy to navigate around, but they have no character. Sometimes it's good to get lost in a tangle of streets when you are on foot. You never know what delights might be tucked around the next corner.