The Echo Tunnel

The title refers to the extra.

When our boys were small, perhaps 3 and 5 years of age we used to have regular family walks from the road end at Fersit up to Treig Dam; to the "Echo Tunnel". The West Highland Railway line, Fort William to Glasgow passes along the east (opposite) bank of Loch Treig and if a train went past we would wave to the passengers. Maybe that was just me.,
Treig Dam is another of the water abstraction sources for the aluminium smelter in Fort William and from here a tunnel runs 15 miles through the mountains to Fort William. The Loch Trieg abstraction point is about a mile from the dam and the tunnel enrtance never gets exposed. There is a compound adjacent housing a winch system to open and close huge valves at the base of vertical shafts on to the tunnel.

Treig Reservoir is often quite low and when in this state it is easy to walk down the dam which is actually formed like a gently sloping revetment to see what we call the "Echo Tunnel". It is actually the entrance to a  large valve which I imagine can be used to release water to manually lower the loch level for inspection or maintenance. Whatever; when you shout in to it you hear your own voice bouncing around its walls for several seconds.
On our walk today, Mrs SJR, S, Caley and I, it was only me who felt the need to once again check out the Echo Tunnel. Actually Caley expressed some interest too.
The main picture is taken near the valve compond on a rock outcrop above the tunnel mouth.