Birmingham & Fazeley in Curdworth

I enjoyed my farm trail around Curdworth so much i headed along the canal into the village itself. I have been this way once before, its a very nice spot and also has a cool short tunnel (52m). I wonder why they built the tunnel instead of cutting through like they did elsewhere, it doesn't seem like there was anything built on top of the tunnel, or maybe there was once but now its gone? Anyway photos are here.