The B390 follows a route across part of Salisbury Plain. The road was originally part of the A344 but as part of the continuing downgrading of that road it became the B390 in the 1970s. Don't tell everyone, but the B390 is a useful alternative to the A36 / A303, especially on a dark wintry night when the A303 is unexpectedly closed!
The road starts on the A36 just south of Heytesbury and climbs up past the razor-wire fences of the army barracks. These are soon passed, however, and the road opens out into wide straights with good sight-lines over the low banks on either side. Whilst giving the impression of being a level route, the ascent and subsequent descent into Chitterne are separated by a relatively short level section across the top of the hill.
A steady drop leads to a sharp left-right and into the pretty village of Chitterne. The road winds through, crossing a little bridge, and then starts the climb up onto Chitterne Down. This section of the route is largely unfenced, with regular 'Tank Crossing' warnings, but thankfully few tanks! A long gentle descent drops us down onto the A360 just north of Shrewton, and from here it is a quick run to the A303, with a choice of routes.