There are two tunnels at Harecastle, where the summit level of the Trent & Mersey Canal crosses the watershed that its name implies. One, built by Brindley and opened in 1777, has long been out of use and today all boats use Telford's "new" tunnel, opened in 1827.
A one-way system operates through the tunnel, with entrance controlled by tunnel keepers. On arrival, the keeper at the northern portal asked us to tie up as close to the entrance as possible as he was expecting four or five other boats: in the meantime we had to wait for four northbound boats, that were already in the tunnel, to come through.
As can be seen from the photo it's a tight turn into the tunnel from the top end of the waiting area, but I was pleased to be given a verbal "10 out of 10" for my manoeuvre into the tunnel mouth by the keeper. Unfortunately, seconds later, the chimney that I had carefully removed from its collar and placed on the cabin step for the passage fell over with a clatter and I had to stand on it quickly to prevent it rolling off the counter and into the water! Needless to say, this meant I lost concentration and the bows hit the tunnel wall - which no doubt led to an immediate downgrading of my score.
The rest of the passage was incident-free as the tunnel is straight and relatively easy to navigate, especially as you can be certain there will be be no oncoming boats. Towards the centre, subsidence has brought the roof down rather low (hence the removal of the chimney) and the steerer of a traditional stern boat has to stoop whilst steering until past the low section. Uniquely, as far as I am aware, Harecastle tunnel has a door across its southern portal to control the ventilation system and allow its use by powered craft. This is rather disconcerting as unlike other tunnels there is no sign of the exit from inside - instead you come across a "STOP" sign seemingly in the middle of the tunnel. As you approach the sign however, the door magically opens and reveals the southern exit and the canal beyond. Our passage of the 2,926 yard (2,676 metre) tunnel took just 33 minutes at an average speed of 3.04mph (including the bump on the way in!).
Southern portal of the Harecastle Tunnel, presumably rebuilt in 1954 when the ventilation door was installed.
I daresay that at the moment, with the Shropshire Union closed at Shebdon, many boats will be making an unexpected diversion along the Trent & Mersey and through Harecastle - and I hope they enjoy it as much as I did.