From Roader's Digest: The SABRE Wiki
|City of Edinburgh Bypass|
|Length:||12.8 miles (20.6 km)|
|Meets:||A8, M8, A71, A702, A701, A772, A7, A6106, A68, A1|
|Route outline (key)|
The A720 provides a dual carriageway City Bypass for Edinburgh and has taken its number from the old city centre avoidance route which was cobbled together from suburban routes to provide a link between the radial routes such as the A7, A701, etc., although it never connected directly to the A1. This route is still complete, numbered as the B701 (which incidentally is its original number), and indeed as recently as last year there were still a few signs marking it as the A720. The A720 was considered by Edinburgh City Council as a possible outer cordon of the congestion charging zone which if implemented would see a proliferation of "Park and Ride" centres and parkway stations for trams or trains at each of its intersections.
Gogar – Juniper Green
The A720 begins at a large, semi-grade-separated roundabout with the A8 at Gogar. Many would argue that it should start at the A90 Queensferry Road but that's another discussion. The junction has a couple of free-flowing links that provide access between the A8 and the South Gyle Broadway and South Gyle Broadway and the Edinburgh Bypass. It is good to see Edinburgh Council getting its priorities right by providing easy access to the Gyle shopping centre. All other movements are via the roundabout which (as far as I know) is always signal controlled. A couple of interesting features of this roundabout are the police slip (like those on motorways) on the northern side and the underpass provided for the A8. The underpass has been constructed as 2-lane dual but to ease flow from the bypass heading into the city it is squeezed into a single lane to allow a cleaner merge. The A720 is partially a Special Road and as such the entrances of the roundabout have signs indicating prohibited traffic with the ubiquitous small wooden fence indicating where restrictions apply. Because of the specialness, this junction, like all others on the city bypass, have special signs indicating a route for cyclists that provides a suitable route. This basically follows the original route of the A720 (B701).
The City Bypass starts as a dual 2-lane carriageway heading south with a third merge in line from the Gyle Centre access. Almost immediately we reach the A71 junction for Kilmarnock (and Heriot Watt University!). This junction is very peculiar as the proximity of the M8 Hermiston Gait interchange (built in 1995) prevented the former slip roads of the A71 joining the bypass. The carriageways were then just extended round the M8 interchange to rejoin the A720 further north. The A71 slips have also been hijacked to provided a belated free-flow link between the M8 and the A720 north. This has meant that for a period of about a mile we have perhaps the widest piece of tarmac in the East of Scotland (up to 15 lanes!). The main link between the M8 and the A720 is provided by a large signal-controlled roundabout. The M8 junction has the distinction of being one of the few places where Special Road to Special Road traffic has to give way to traffic from an unclassified road from a retail park!
The landscape contrast at the west end of the City Bypass is very interesting. As the bypass provides the de facto limit of [[Edinburgh] and the beginning of the green belt the land to the west is open farmed countryside and the land to the east is completely developed. It is slightly odd to be standing in a field on the west side and seeing the developed edge of Edinburgh less than half a mile away with no sort of gradual development in between. The land south of South Gyle Broadway, Edinburgh Park, has only started to be developed in the last few years and is full of modern glassy offices – it will be very impressive when completed. This land was released from the Green Belt when the bypass was constructed.
Just past the M8 junction we pass underneath the Union Canal aqueduct which for years stood isolated from the rest of the system due to various obstructions in Sighthill and other places but has recently been reopened as part of the Millennium Link. If the traffic on the M8 gets too much you can also commute to Glasgow by boat! We now pass underneath the A71 Kilmarnock road and through the suburbs of Baberton and Juniper Green. There is no direct connection between the A720 and the A70, which has left that road nice and quiet, although heading north there is an indirect connection via the B701. There are two reasons for this lack of junction, firstly the land is very developed here and the construction of slip roads and a roundabout would have involved the demolition of many properties, and this is an expensive area where people know their rights. The large retaining walls that squeeze the carriageway show the difficulty putting the road through. In addition, to the south of the junction the road crosses the Water of Leith which although a small river has quite a wide valley. The expense of providing additional bridges (cf. A77 east of Kilmarnock) or a wider bridge to support the slip roads would have been prohibitive for such a quiet access. In addition I suspect residents alongside Lanark Road (the route into the city) would not have been pleased with the extra city-bound traffic a connection would yield. The A70 is the last remaining 4-lane route into the city that for at least part of its length has no bus lane – indicating its low priority.
Juniper Green – Lothianburn
Once over the Water of Leith the road and its surroundings change dramatically. The road changes through the addition of full motorway-sized hard shoulders equipped with phones and a big warning sign saying that it's for emergencies only. The hard shoulder begins immediately south of the Water of Leith bridge and was completed about 2 years ago in response to the problems caused by the all-too frequent accidents that occurred around here. The hard shoulders were constructed cheaply and most of the space for them came from the central reservation which has been reduced to a single row of jersey-style barriers. Around us we see the Pentland Hills crowd up to the edge of the bypass and looking south it is hard to imagine you're on the edge of the city. The northern side is fringed by the back gardens of suburban housing. A lot of trees have been planted on the south side of the bypass to provide screening for the few properties around Swanston. It is sad though that these block the attractive views of the hill. The construction of the bypass was routed through a major infrastructure corridor to minimise environmental damage so we are shadowed by multiple sets of pylons.
The next junction is with the Dreghorn Link. This was a short purpose-built road to provide access between the B701 and the bypass and is indeed the only purpose-built link. The Dreghorn Link was important as it provided access to the large barracks in the area and relieved the residents of Colinton of these passage. Frequently when driving this route I passed many military vehicles. The link is pretty impressive as it required the construction of a deep cutting to link it to the B701 – it is classified at 30mph though which is very slow considering its high standard – though it does set the tone for Edinburgh driving. The western on-slip for the link is interesting as it is two-way with local farm traffic only leaving it less than 100 yards before it joins the A720 directly. The Dreghorn junction provides access to the western City Bypass services.
Continuing to the A702 junction we keep the hard shoulder, although it ends just in advance of the A702 overbridge. The hard shoulder ends with an abruptness that indicates that the intention is to continue it further. The A702 junction is signed as the main southern route to the M74 and Carlisle, and leaves on a long double-laned slip.
Lothianburn – Sheriffhall
Continuing east the landscape changes dramatically. To the south we can see the new office parks of Bilston (a technology park, apparently) while to the north the suburbs that have been shadowing the road since we started in Gogar suddenly recede away and indeed it is difficult to see the city. The open countryside so close to the city centre is very surprising and appreciated. Because of this we can get a good view of Arthur's Seat, whose size and dominance of the landscape becomes apparent for the first time. With the demise of the hard shoulder we are back to emergency lay-bys with each one being numbered to provide the emergency services with a precise location. This stretch of road has the potential to be altered significantly if Midlothian Council gets permission to construct a dual carriageway upgrade to the A701 that will bypass Bilston and Straiton and provide easy access to Penicuik. The purpose is to capitalise on the city's economic dominance of the area and encourage people to move into its jurisdiction. Needless to say this is being opposed vehemently by the environmental groups.
The actual A701 junction is an exact copy of the A702 one: a pair of small roundabouts linked by a dualled road. The only difference is that the A701 goes under the bypass whereas the A702 goes over. Beyond the A701 junction the southern aspect becomes a lot more rural but almost as a direct response the northern city side become visible again due to the presence of large multi-storey blocks (about ten storeys) which punctuate the landscape. On the left side a small disused railway line is visible, which used to service the mines of Midlothian but has not been used for what seems like ages. The Lasswade junction is a bit of a mystery to me. It provides limited access to an unclassified local road with no apparent primary destination. Any destination it does serve could be well served by the junctions on either side. The only plausible reason I can think of is this junction acted as a temporary terminus for the bypass while it was being constructed and has never been removed. However, this seems remote as the next junction for the A772 (former A7) at Gilmerton also seems to serve that purpose and to have two temporary terminus junctions so close together seems to be unlikely.
The A772 junction is very odd in another way - it looks like it was planned to provide full access to the bypass but these plans were abandoned later. On the north-eastern side of the junction there looks to be a partially built (or abandoned) slip road and the alignment of the A772 on the south side, where it doubles back and approaches the bypass seems to suggest this also. The landscape to the north of this section is fairly unattractive due to the copious amounts of what look like mining spoil and the presence of the decaying railway and industrial units.
The A720, A7, A6106 (and former A68) junction is infamous and it deserves its reputation. SABRE has had many discussions on the reasons for its apparently dreadful design but the main reason seems to be a result on unstable mine workings underneath, which couldn't withstand bridges. This is plausible but why they didn't use a concrete raft (as on the M74 stretch in South Lanarkshire) seems to be a bit mean. The junction is always horribly overloaded and can often have tailbacks that stretch for half a mile in every direction. Initially the roundabout was not signal controlled but this meant that traffic on the other roads could never get onto the junction due to their relative quietness. However it did make the bypass comparatively free-flowing. Traffic lights were constructed to force bypass traffic to yield which left it in the current mess. As many have suggested the only appropriate solution to this junction would be to provide an overpass for the A720. I think Sheriffhall intersection must be high up for the coveted "Switch Island of Scotland" award. It is interesting to see how much busier the A6106 is getting as it provides a quick short-cut to the Fort Kinnaird shopping centre – expect to see more traffic calming soon.
Sheriffhall – Whitecraig
Most of this section is raised on an embankment and provides some of the best views on the whole bypass. To the south there is the Dalkeith House country park (which incidentally stopped the Dalkeith Northern Bypass) and to the east you get a panoramic view of the Lammermuir hills. The area feels very rural now as the city has not developed that much in the east. This may change soon with the intention to construct a huge new housing development at Danderhall. The immediate surroundings of the bypass are much less interesting, being very flat and scarred by industry. This section of the bypass is like the rest dual 2 lanes with emergency lay-bys, but also has a ghost bridge. The bypass crosses over the former route of the Waverley railway line to Carlisle which if campaigners get their way could be reinstated to Galashiels in as little as 5 years. The penultimate junction on the road is another dumbbell, with the A68 Dalkeith northern bypass, which we used to meet at the Sheriffhall roundabout.
We finally cross into East Lothian and see the large embankment of the A1 ahead of us. The terminus of the A720 is similar to how it started: a large roundabout with the cross road given grade separation, although it is not signal controlled. Adjacent to the roundabout are the road's eastern services. Above us the A1 becomes a special road at this junction and with the A720 a special road, all restricted traffic has to have an escape route. This escape route is provided by the roundabout being unrestricted and a small single-carriageway link to the B6415 and therefore access to Musselburgh. This link road's number is debatable: in this direction it's signed as the primary B6415 whereas in the other direction the A1 and A720 are given equal billing. Like the Gogar and Sheriffhall roundabouts this one has bad congestion and should really have direct free-flowing links providing direct access between the A1 West and A720 West, and A720 East and A1 East. What the A720 really needs is for all its roundabouts to be removed!
The need for an Edinburgh southern bypass was known in the 1960s, when the B701, a road which connected the A71 and A701 on the edge of the city, was lengthened and upgraded to Class I status, becoming the first incarnation of the A720 in this part of the country. A better road was clearly needed, however, and the route currently known as the A720 was built and opened in sections between 1980 and 1990.
The Colinton section (A702 to Baberton) opened first, in 1981, with the Dreghorn junction opening circa 1985 when new housing and the service area was built there. Next up was the Sighthill section (Baberton to A8 at Gogarburn) which opened in late-1986. 1988 saw two sections open: the Burdiehouse section (A702 to A701) in the summer followed in the autumn by the section between the A68 at Sheriffhall and the A1 at Old Craighall. This left the Gilmerton section (A701 to A68 at Sheriffhall) which opened at the tail end of 1989.
As each new section opened, the previous route was renumbered to the B701, though the Sheriffhall-Old Craighall link was a completely new section of road.