Armitage Tunnel.

When is a tunnel not a tunnel?  When it is Armitage tunnel!  It was a tunnel once but local mining caused subsidence which made it unsafe.  The easiest way to deal with this was strip the top of the tunnel away leaving only a"gorge" with a rather large bridge at one end.  The bridge is so large the effect is almost tunnel like.

The problem with an ex-tunnel is, like many tunnels, it was designed to be one way.  In the days of horse drawn boats this wouldn't have been too much of a problem, looking down a tunnel you would easily see the silhouette of the boat and horse.  With no top on it isn't so easy to see if something is coming.  The Canal and River trust advise sending a 
crew member on ahead to check.  Normally we send a crew member with a walkie talkie, however somebody ( one of a pair of blippers) forgot to pack them.  So on this occasion Clickychick (using her new found 
fitness) jogged through the "tunnel" to relay a message to me halfway along.  I could then signal to "The Mate" to bring Solace through.

The blip shows Solace coming through the "tunnel" for reasons which escape me, "The mate"  has the tunnel light switched on.  A bit of overkill in my opinion considering the light is for seeing when in a tunnel!

A final thought.  The stacks of toilets we see in the factory suggests this is the home of "Armitage Shanks".