TUESDAY, November 12, 1968, was a chaotic day in Glasgow’s Clyde Tunnel.

First, the northbound tunnel was closed to traffic after a dustcart ripped off 25 yards of aluminium sheeting on the roof, damaging ventilation ducts (pictured). The accident, at 6.30am, caused substantial tailbacks of over a mile on either side of the river.

The southbound tunnel was rapidly switched to two-way traffic. It worked well for a few hours - until a car broke down in that section, creating further problems.

Then, at the busy lunchtime period, an articulated lorry jack-knifed in the middle of the tunnel and collided with a car, injuring its driver. As police and firefighters tried to get the two vehicles out of the tunnel, specialist engineers were making repairs to the roof of the northbound tunnel.

Police diverted all traffic entering the tunnel approaches from the south as far back as three-quarters of a mile, which led to enormous congestion in Paisley Road West and the Clyde bridges.

By 5pm, both Clyde tunnels were reopened and running smoothly, but motorists, anticipating a lengthy closure, had sought alternative routes, which is why the rush-hour traffic crawled over all the river’s bridges. A half-mile queue built up at the Renfrew ferry, causing an hour’s delay in crossing. Further congestion was caused by the Erskine ferry being closed for an overhaul.

All told, the 12 hours of traffic chaos that day were the worst the city had encountered for many years.

“It has been one of the worst days I have ever known,” an A.A. spokesman said with feeling. “We have been inundated with calls from motorists wanting to know whether the Clyde Tunnel would be operational by the evening.”