Pouilly-en-Auxois, as I noted on our arrival, is at the very top of the Burgundy Canal however it is not exactly at the top of the mountain, so to get to the other side we must aim our little boat at what seems like an even smaller black dot on the side of the mountain. If we manage to do that, we become enveloped in darkness (except for the bits where the tunnel lights are working), so the next navigational activity is to take aim at the tiny speck of white light three and a half kilometres away and attempt to hit it without hitting anything else in the meantime.
Driving through tunnels is not a terribly fearsome thing, but it does require a good deal of concentration as even for a small ship such as ours the fit is quite snug. For instance in the case of the Pouilly Tunnel, at the point where the curve of the roof has two metres of headroom, a little less than the total height of our boat, it is exactly five metres wide. We have seventy centimetres clear each side so there is not much stress while concentration lasts, but for those who pilot the five metre wide commercial ships, there is no substitute for precision!
Eventually, all good things and tunnels come to an end, and when we emerged the world seemed to be a different place full of blue sky, sunshine and castles.
Welcome to the valley of the Ouche.