The A31 has largely retained its original route (apart from the middle section), but is a dramatically different road today, with many upgrades and rebuildings over the years. This page provides a full account of those changes.
Guildford - Winchester
Bypasses aside, this section of the A31 still follows its original route. Back in 1922 the road started in the centre of Guildford on the A3 London Road, opposite the original western end of the A25. It headed west along York Road and Onslow Street to join its current route near the station. Construction of the Guildford bypass in the 1930s declassified York Road but the A31 still started in Guildford, albeit now on the wrong side of the A3.
The Farnham Bypass opened around 1945 as a single carriageway road. It was later widened to dual carriageway, except for the bridge underneath the A287 which was not built to take four lanes of traffic. The current arrangement provides two lanes westbound and one eastbound. The road either side of the town was upgraded online in the 1970s. The Bentley Bypass opened in 1995.
The Alton and Chawton Bypass opened in 1970. The original route diverted from the current one at Cuckoos Corner in Holybourne and ran along London Road, High Street and Butt's Road through the town centre. After the town centre the road passes under a double railway arch the original A31 and A32 continued straight on here along Winchester Road, however, this has since been closed to motor vehicles (under the current A31). This road comes out in the centre of Chawton at Jane Austin’s House, where the A31 swings off to the right with the original A32 continuing straight on, after this old and new A31 continue until the Alresford Bypass.
The New Alresford and Bishop's Sutton Bypass was opened on 17 December 1986; unlike the 1970s improvements, it is single carriageway. It starts to the ast of Bishop’s Sutton where a roundabout takes the bypass to the south of both Bishop’s Sutton and Alresford. The original route follows what is now the B3047 through Bishop’s Sutton and Alresford, the bypass re-joins the old A31 at a roundabout south-west of Alresford.
At the Winchester end, the road entered the city along Alresford Road (now the B3404). When the bypass was built (originally numbered A33) the A31 crossed it on the Spitfire Bridge and so access to it was via the A272. In the 1970s a southern bypass was also deemed necessary - but one was cobbled together out of pre-existing roads rather than constructing one. The A31 was therefore rerouted along part of the A272 to reach the A33 and remained on this route when that road was upgraded to motorway, becoming the M3.
Winchester - Cadnam
The A31 originally left Winchester along Romsey Road (now the B3040). However, to complete the Winchester southern bypass mentioned above, the original A31 west of Winchester was renumbered A3090. The A31 route instead multiplexed along the A33 (which was dominant) south of the city into Otterbourne from where it took over the former B3057 to reach its original route at Hursley. When Otterbourne was bypassed by the A33 the A31 took over its pre-bypass route into town.
From Hursley the A31 continued west via Ampfield to Romsey, which was later given an S2 bypass. From there it continued southwestwards to Ower and a short multiplex with the A36. This section was dualled ready to join the new M27 and a slip road (just possibly the A36(M)) was built to meet the motorway at J2. The M27 then continued west of here parallel with the A31 as far as J1.
In the 1990s the M3 was completed between Winchester and Southampton. This severed the line of the A31 at Otterbourne and it was decided not to replace it. This section of road was declassified and the road west via Romsey to the A36 in Ower renumbered as an extension of the A3090, thus signing through traffic along the M3 and M27 to rejoin the A31. The remaining section of A31 between Ower and Cadnam was not downgraded even though there is no obvious route from the M27 to A31 at Ower.
During the late forties, there was heated debate with the Verderers, fierce protectors of the New Forest, about providing a much needed upgrade to either the A31 or A35 through the New Forest, thus providing a proper link along the south coast. Eventually, in the 1950s, the A31 was controversially selected to be upgraded and was progressively upgraded over the next 20 years.
The section of road between Cadnam and Stoney Cross (around 2 miles) was first to be dualled in the mid-1960s. The westbound carriageway of this section is the original road, as shown by the narrow lanes and tight bend. At Rufus Stone, there is also an at grade junction which usually has long tailbacks as people try to cross the eastbound carriageway.
Between Stoney Cross and the edge of the New Forest west of Picket Post, most of the road was upgraded in sections between 1966 and 1972, but with the building the M27, there was some impetus to get the job finished. The last section to be dualled, immediately west of Stoney Cross, was finished in 1975, along with the removal of the at-grade junction at Bratley, which required the rebuilding of the recently built dual carriageway.
At Picket Post, there is a grade-separated junction with the Burley road. When the A31 was dualled, this junction was left as a flat junction and became an accident blackspot, so it was grade-separated in 1991.
Ringwood was originally the crossroads for the A31 and A338 Christchurch to Salisbury road, and as such, became very busy. The A31 and A338 have been upgraded on 4 occasions, and the job still isn't finished today.
Originally, the A31 entered Ringwood along Southampton Road, with the A338 joining near where B3347 crosses today, multiplexing for 100 yards or so, before splitting again in the centre, with the A31 turning westwards along High Street and the A338 going southwards as Christchurch Road. Sometime before 1949, probably in the 1930s, an A31 northern bypass was built. This started where Southampton Road today crosses over the A31 and follows the course of the modern road, around the northern side of Ringwood, but was built as single carriageway. The A338 joined at a T-junction, roughly where today's grade-separated junction is, and the A31 carried on to cross over the River Avon to rejoin the original course of the road at West Street. At the same time, the A338 north of the town was rerouted slightly westwards as the old road was narrow and no longer suitable.
In the late 1960s, the A338 Bournemouth Spur Road was built, running up the west side of the River Avon, replacing the old road, which ran up the east side of the river and started in Christchurch, thus reflecting the relative changes of importance of the two towns. The new A338 joined the A31 at Ashley Heath and so removed the road from the centre of Ringwood. As the same time, the A31 was dualled across the River Avon, which involved building a grade separated junction with the B3081 (destroying the formation of the old railway in the process) and building a second bridge across the river. The A31 returned to single carriageway once across the river. As the A338 multiplexed with the A31 to cross the River Avon, the short section of single carriageway up to the junction with the A338 caused a lot of congestion.
By the late 1970s, the A31 was dualled across the New Forest and westwards from Ringwood, but the old, single carriageway bypass around the north of Ringwood, now also carrying the A338 traffic, was causing a huge bottleneck, so a new Ringwood bypass was built, opening in 1977. The new dual carriageway was built from the edge of the New Forest and down Poulner Hill on the existing alignment. At the bottom of the hill, the road diverged from the old Southampton road and ran in a cutting along a more southerly alignment through Ringwood. Whilst some of this road was built on unused land, some houses were demolished and several roads cut off, although demolition was limited by building several retaining walls. The new road then took over the course of the old bypass and dualled it, as well as creating a grade-separated junction with the A338. The final part of road involved squeezing in a second carriageway between the river and the parish church, which involved building over part of the graveyard. Due to lack of space the westbound onslip is very short and on the inside of a curve resulting in poor sightlines.
The final upgrade was made in the late 1990s when the Ashley Heath junction with the A338 was grade separated by running an underpass through the roundabout. To improve traffic flow, both carriageways were widened to 4 lanes, but whilst the eastbound carriageway was widened for the entire length between the two A338 junctions, the westbound carriageway only gained the 2 extra lanes at the B3081 junction, leaving the poor onslip from the A338 and dual carriageway past the church.
St Ives and St Leonards
The A31 through St Ives and St Leonards was progressively dualled during the 1960s, mostly by adding a new carriageway next to the existing road. The scheme started just where the eastbound off slip for the B3081 leaves the road today. This sliproad, along with the eastbound onslip, is the original road and crossed over the Ringwood to Poole Railway here. The first stretch of dual carriageway didn't last very long because the rerouted A338 Bournemouth spur road and large roundabout arrived within a few years of this section being dualled. The A338 junction was originally a plain roundabout junction, but this was grade-separated in the late-1990s.
Originally, the next section of dual carriageway through St Ives was constructed by adding a second carriageway to the south side of the original road, as the village fronted the north side of the road. Due to these frontages, another new carriageway was built to the south of the first new carriageway and the old road made into an access road. At the Brocks Pine Roundabout (today the first roundabout from London), the original road is still on the north side, as shown by the number of side roads joining, but as St Leonards peters out, between Oaks Drive on the north side and Beech Lane on the south side, the new carriageway swaps sides with the north side being the new one. At the Boundary Lane roundabout, the new carriageway again changes over to the south side as the road doesn't line up either side of the roundabout, and the side roads are back on the north side. At Tricketts Cross, a large roundabout was built for the Ferndown Bypass in 1986 and so today, the A31 turns right and heads north. Originally, the A31 carried on up the hill to another roundabout for the junction with the A348, but this section was reclassified as part of the A348 when the bypass was opened.
From the Tricketts Cross roundabout, the A31 used to run dead-straight along Wimborne Road, now a minor road, through the northern part of Ferndown and Stapehill, to Canford Bottom.
The Ferndown bypass was built in 1986 as a loop around the north of Ferndown. The first section from Tricketts Cross, crossing the B3072 and up to Ameysford, was built as dual carriageway, with the rest built as single carriageway. The roundabout separating the two sections is fairly small, links to the Ferndown industrial estate and is today a huge bottleneck. The reason for the seemingly strange split is that another road, the Ferndown Relief Road, was planned to start from this roundabout and head south. This road was planned to cross the River Stour between Hampreston and Longham, cross the A341 outside Bearwood, and carry on over Canford Heath to join up with the A3049 at the northern edge of Poole, which explains the odd right-hand turn in that road on Canford Heath. The Ferndown Relief Road was planned to follow on from the Ferndown bypass, but got delayed and then cancelled because of environmental concerns. The road was reborn in the mid 1990s as one of the options for the A31 Poole link road, but this scheme was cancelled by the new Labour government in 1998, although the local councils in the area continue to pursue various options for improvements in the area.
From Canford Bottom, the A31 used to go through the centre of Wimborne Minster along what is now the B3073 and B3078. Due to the narrow roads, there was a one-way gyratory around and through the centre of Wimborne. The A31 came in on Leigh Road and the one-way system started at Lewens Road (Rodway is a modern addition). The junction with Poole Road used to be the, tight and traffic light controlled, junction with the A349. The A31 then crossed over the River Allen on East Street and carried on along King Street to the crossroads with the B3082. The A31 turned left and headed out of town on Julians Road, what is now the B3078, whilst the one-way system turned right onto West Street and headed into the town square. The road turned left along one side of the square and headed northwards along West Borough before turning right onto Priors Walk and then Hanham Road. Crossing the River Allen again, the road turned right again onto Rowlands Hill and then Lewens Lane to rejoin the original route.
In 1981, the single carriageway Wimborne Minster bypass was opened from Canford Bottom to Lambs Green, built by Sir Alfred McAlpine. The bypass has a single junction in the middle, with the A349, which was rerouted down a short link road, with the original road into Wimborne being reclassified as the B3073. The western half is built close to the formation of the original Somerset & Dorset railway from Blandford Forum to Wimborne. As this section closed in 1928, it is difficult to say that the road was built on the railway, but the B3073 overbridge was built in the same location as the railway overbridge, although it is not clear whether the bridge still existed when the bypass was built.
As the bridges on the bypass were constructed in 1981, they each carry a stone plaque with the date 1981 and the initials "C" and "D" in the top left and bottom right corners, to commemorate the wedding of Princess Diana and Prince Charles.
Wimborne to Bere Regis
After the Wimborne Minster Bypass, the A31 is largely original. Although there have been minor tweaks here and there, to widen the road and ease some of the bends, there are no more bypasses or dualling. Today, the A31 terminates on the A35 Bere Regis bypass where originally the road carried on into Bere Regis to meet the A35 at a very tight crossroads in the centre of the village.
Just west of the hamlet of Winterbourne Tomson, there is some evidence of an aborted widening scheme. Looking here on Google Maps show a double fenceline to the north side of the road with space to add a second carriageway. As this is a straight piece of road in the middle of the countryside, it is unclear why a second carriageway would be needed compared to anywhere else on this stretch of road. No other information has been found about this, but the evidence does point to a road improvement.