From Roader's Digest: The SABRE Wiki
|From:||Glasgow Airport (NS467654)|
|To:||Shewalton, near Irvine (NS330365)|
|Length:||25.4 miles (40.9 km)|
|Meets:||M8, A726, A761, A760, A738, A78, A736, A71, A78|
|Former Number(s):||A740, A78|
|Old route now:||A8, A761, B789, B787|
|Route outline (key)|
The A737 is undoubtedly the most changed road in south west Scotland, and vies to be one of the most changed in the country. Only a handful of its 25-or-so miles remain exactly where they started; it's had bits chopped off, bypasses built, grade separated junctions plugged in, it's usurped other routes' numbers and priority, and it's landed up by accident more than design as the primary route from the Greater Glasgow conurbation to the North Ayrshire coast.
The lost section: Paisley Road West
Originally the A737 used to run right into Glasgow proper, with its eastern end on Kinning Park at Paisley Road Toll. The distance from there to Edmiston Drive in Ibrox was lost to the A8 in the 1960s when the decline of shipbuilding meant the A8 didn't need to serve the Govan Road shipyards any more. Paisley Road West continues through Halfway, Cardonald, and Hawkhead to central Paisley.
The A737 hung around in Paisley long enough to be shoehorned into an inner-city one-way system, and out via Johnstone town centre. Come the seventies and with Paisley now bypassed by the M8 motorway, this part of the route had become crowded and was not taking the weight of traffic well. A plan was drawn up to rectify this with a motorway spur of the M8, running from the then-new airport at Abbotsinch, bypassing the Renfrewshire town centres of Linwood, Johnstone, Kilbarchan and Howwood.
The Johnstone Motorway
The Johnstone Motorway (for which no number seems to have been reserved) plan began with the first two miles from M8 J11 (today's St James Interchange, junctions 28A and 29) to Linwood, opening in the early 1970s without motorway restrictions as the A740, with a temporary tie-in back to the A737 via the A761. But progress from there was non-existent; the other bypasses weren't bolted on until 1992, by which time building motorways had become untenable.
So instead, the A737 was ridden up the new route back to Glasgow Airport to tie into the M8, dispatching the A740 for good, and the pre-bypass route became an extension of the A761 from Linwood back to Ibrox. The cut-off town centre road through Johnstone become the B789, and west of there mostly B787 but some of the road through the more recent development of Milliken Park is unclassified.
The new northern end of the A737 is therefore the aforementioned M8 junction – strictly speaking at the roundabout beneath it with the A726 – and there are direct sliproads running from the Glasgow-facing side of the motorway to the A737. The bypasses are almost entirely dual carriageway standard, except that of Howwood, and there are spacious grade separated junctions with the A761 for Linwood, B789 for Johnstone and B787 for Kilbarchan. Beneath the overbridge of this third junction the second carriageway peters out and there are large ugly signs warning of the two-way traffic.
Howwood and Beith
The Howwood bypass is still a good standard even if it is only single, but after that the road is almost untouched as it climbs up past the reservoirs next to the railway. The crossroads by the Auchengrange coal pits with the Lochwinnoch- and Largs-bound A760 was attracting just too much traffic and was remodelled into the Roadhead Roundabout in the sixties. It has received additional realignment and widening in the last ten years.
The road from here to Beith is not straight nor fast, and the hedges seem improbably close to the road verge. The Beith bypass is the oldest one on the road, dating from the 1920s, and is consequently of a low standard featuring a succession of busy intersections on a road which has been up to this point mostly access controlled. Despite the 50mph limit, the offset crossroads at the B706 junction, coming on the crest of a hill, is a frightener for sure. The junction at the Glengarnock end of town with the B7049 had to be neutered with a roundabout.
Dalry and Kilwinning
The best descriptor for the unmodified sections of A737 must be “winding”. It weaves over continuous hills limiting overtaking opportunities, and one lorry or unconfident driver can create quite a backlog. The Ayrshire coos always seem to butt right up to the fences, fascinated by the (not) speeding traffic. When the road reaches Dalry, there's no more room for bypassing with the town tightly hemmed in along the valley of the River Garnock. The only option is to run into town under a low railway bridge and trundle up the High Street, complete with very sharp left turn.
The Garnock valley at least offers a flatter and straighter route through the North Ayrshire countryside up to Kilwinning. It's a sizeable town – to be honest there have been plenty of them on this route – and certainly due its own bypass. Trouble is, there's a bigger road in this area, the A78 Firth of Clyde coast road, and it gets the 1960s bypass to the south of town. This is fortunate in terms of the A737's existence, because it gets to borrow the road left behind to the east, with the A738 doing the same to the west. The latter though steals trunk status from us, which is surely backwards because Irvine is the target primary destination: the A737 is going there and the A738 isn't!
The new section: the former A78
Back on track, there is now a dual carriageway bypass of both Kilwinning and Irvine, with which the A737 shares a quite peculiar junction at Eglinton Interchange. Twin link roads set off the A737, one forming a LILO and one from a roundabout, both meeting a second roundabout suspended above the A78.
Irvine is quite unlike anything else encountered en route; it is a true New Town and as such the road entering is ruler-straight with few accesses. Once it gets close to what passes for the centre (read: the concrete shopping centre fortress) it doesn't quite know what to do; instead of purposely ending on the erstwhile A71 as it did in Irvine's formative years, it bridges the River Irvine instead at a turning which terminates the A736. Right up until the nineties the A736 was the recommended route from Glasgow to Irvine, but the aforementioned Renfrewshire improvements made the A737 the more attractive proposition.
To perform its duties in its final destination of Irvine, the A737 must spin round an enormous, supposed-to-be-grade-separated roundabout, duck under the aforementioned shopping centre built in the way only sixties New Towns can be, terminate the A71 itself (how's about that for a feather in its cap) and run back to the A78 one more time at Newhouse Interchange to the south of town atop the old Shewalton mines and moor.