networkn:

 

SepticSceptic:

 

It;s so strange  - you crawl to the approach, crawl through the tunnel, and pop out at the northern end, and then the traffic speeds up to at least the speed limit ...

 

 

I'd suggest it's the confined space gives the impression of being closer together. Also an accident in a tunnel is a much less pleasant thing and has a much larger in impact on traffic flow. I'd consider it normal for people to be more cautious. I don't personally feel too worried about it, but I know less confident drivers feel more apprehensive.

 

If I haven't been through a tunnel before, I am more cautious. 

 

 

 

I suspect it isn't dissimilar to the issue where drivers 'speed up' when they get to a passing lane.

I think most of that is caused by the fact that the road is usually a road that indicates cautious driving...until you get to the straight bit where the passing lane has inevitably been sited. Thus, freed from the need to concentrate on the steep/windy/otherwise hazardous road, the drivers subconsciously accelerate.

Of course, there are some ******* who do it just to annoy, but I think the above explanation covers most instances.