Damn near stepped right on the thing. Head was flat, but not raised, when I saw it and recoiled, then reversed rapidly. Spent the next while wondering how I would get past it, until it eventually slithered off the path and into the bushes, head still flattened. Spent still another good while wondering how long I should wait before it might be safe to scamper on my way, as I couldn't see how far off the path it had moved, and I was worried that it might still be very close, but out of sight, and would get spooked as I passed by.