As much as I like getting a glimpse of Stonehenge every time I drive past, I support these plans.
Currently, the road goes from dual carriageway to oncoming traffic, with a limit of 50mph.
Once the traffic gets busy, all it takes is a few people rubbernecking to cause a large slowdown. And the merge at the end of the Amesbury Bypass can take 20 minutes on a bad day.
Adding extra lanes on the surface is unthinkable, and any route around would end up being a silly length.
If I'm reading the plans correctly, this also duals the road past Winterbourne Stoke. So possibly removing the chaos that can be Lonwbarrow Roundabout.
I'm not sure what you mean?
It's a two-part problem, the road going from dual carriageway to single, and people wanting to grab a look on the way past.
Stonehenge is a unesco site on a plain, so widening the existing road, or planting a huge row of trees, is not going to go down well with the druids.
Getting the road out of site (by either tunnel or diversion) will go a long way to de-modernising the surroundings. (And a fun fact: Half of stonehenge was underpinned with concrete in the last century! So any ways to make it more natural are a plus.)
Stonehenge, by it's nature, can't be viewed outside of it's context. To view Stonehenge is to view it in its environment. It's appeal comes from being part of the landscape, rather than just placed in it.