The Second Alert is:
Book I (The Midlands) - Section 13
Over the last couple of years one of the two towpaths through the Netherton Tunnel has been closed leaving no choice but to follow the remaining one through the tunnel. As it happens this is the first one you come to so for those wishing to walk through the tunnel from the upper canal follow the steps down to the south-eastern towpath of the lower canal and go left to the tunnel entrance. It is hoped that the other towpath will be available at some time in the future but, as ever, it all comes down to money!
Importantly if you intend to go through the Tunnel don't forget to bring a torch, plus some spare batteries !!!!!