By a correspondent
Indications from an official survey pin the famous Stonehenge traffic jam and local traffic ills on a westbound bottleneck on the A303 west of Countess Roundabout, where two lanes become one at a point 1.25 miles (2.00 km) inside the World Heritage Site (WHS). If we focus on this foremost problem, the situation and obvious solution becomes remarkably clear cut.
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The WHS is 3.5 miles wide so only a 2.25+ mile tunnel avoids damage (of massive tunnel entrances, minimum 0.5 miles of new 4 lanes, plus an unknown effect on the water table). The obvious cheap relatively instant solution that will cause least archaeological damage (if detours are deemed impossible and a long tunnel prohibitively expensive) is a second westbound lane added by altering near as dammit the current footprint. Inducted as a clearway, 20,000+ travellers every day still get to glimpse the stones and the English Heritage/National Trust island theme park won’t exist purely for the mere 400–5,000 daily paying customers. The National Trust can always add a temporary A303 pedestrian underpass below the causeway at Stonehenge Bottom (a private one stands near Vespasian’s Camp) and we can spend the next 5-10 years campaigning and saving for a 3.5+ mile tunnel.
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SH Extra Lane