A413

The A413 runs from within the M25 to south Northamptonshire.

Route

The Misbourne Valley

The A413 passing under a railway viaduct in the Misbourne Valley

Leaving the A40 just east of Denham, the A413 begins as a well-aligned rural dual carriageway. With a wide, tree-filled central reservation and laybys, the road's former trunk status is in evidence here. After passing under the M25, it passes under the railway viaduct carrying the Chiltern Main Line over the Misbourne valley. The 2-mile-long stretch of fast road come crashing to a halt at a roundabout with the B416 (formerly A332). The D2 continues as a through-pass through Chalfont St Peter, before ending at a roundabout next to the village centre and degenerating into semi-urban S2 through Chalfont Common and Chalfont St Giles. In Chalfont St Giles, there's a double mini roundabout with the B4442 and the road to the village centre.

The A413 Amersham bypass

Upon leaving the Chalfonts, the road gets more rural for a short while, before meeting the junction with Cokes Lane (which leads to Little Chalfont) and then hitting the edge of Amersham. The A404 goes off to the right, eventually to west London, the former A413 ahead is now numbered A355 and the A413 bears left, to bypass Amersham Old Town. The A355 is met again at the next roundabout and the A404 at the one after, from where it heads down to High Wycombe.

The bypass ends at the next roundabout and the A413 becomes dual - not for long, though, as it narrows once more to bypass Little Missenden. It then bears right to go under the London to Aylesbury railway line and bypass Great Missenden. The B485 (to Chesham) and A4128 (to High Wycombe) are met at successive roundabouts. The River Misbourne rises not far from Great Missenden so we now leave our companion behind and climb into the Chilterns, although the road is not particularly steep as it passes through a gap in the hills.

si404 rewriting section... check back soon.

Over the ridge

The A413 alongside Wendover Station

The gap the A413 finds is also followed by the railway; it is fairly straight and fast, cutting between Coombe Hill (near Chequers) and Wendover Woods - the two highest points in the Chilterns. The A413 used to go through the middle of Wendover, but now it follows a bypass (the last to be built along this route). This bit of wide S2 starts on a new roundabout that goes over the railway, then drops down to run directly alongside it. it's easy to end up doing 100mph going northbound as it's downhill, into the Vale of Aylesbury. The Ridgeway crosses just before the station. The bridge is odd, one half old and the other half new. The B4009 meets the Wendover Bypass at a roundabout and heads north in a multiplex (despite it facing south). It then heads south along the old A413 at the next roundabout, after recrossing the railway. The A413 gets urban and we enter Stoke Mandeville. The B4544 heads from there to Weston Turville and the newly-bypassed Aston Clinton, and the A4010 to Princes Risborough and High Wycombe meets us, though it's quicker to take the B4009 or the B4443, which meets us in a bit. The road enters Aylesbury and meets the B4443, where the A413 becomes dual carriageway once more. It hits the Aylesbury ring road and multiplexes with the A41, and then the A418, whereupon it loses its primary status and heads north.

Lez Watson writes:

The A413 approaches Aylesbury town centre along Walton Street meeting the A41 from London at the roundabout next to the County Hall building. This was the town’s first, and last, ‘skyscraper’ – an object of much derision over the past forty years. The A413 is then subsumed into the A41 along the dual carriageway as far as The Hen & Chickens pub where it turns right at the comic double roundabout and up Oxford Road (still the A41 but now non-primary along this short length) to the top of the hill. Here the Royal Buckinghamshire Hospital (my birthplace) looks over another double roundabout where the A41 turns off west while the A413, non-primary for the rest of its length, heads along Buckingham Road to the edge of town. Two more roundabouts are negotiated before the road finally leaves the town, passing on the right the Holiday Inn and Watermead, a large thematic housing development from the 1980s.

Beyond Aylesbury

Having left the town the road reverts to its pre-motorway era condition to Winslow, via Hardwick and the attractive, if traffic laden, village of Whitchurch. The curious can turn right just before the village and drive through Cublington to Wing airfield, site of London's proposed third airport in the 1960s. There's only a hint now of the runways and buildings of the former wartime bomber base. Back on the route the A413 sweeps through Aylesbury Vale to the edge of Winslow where it is joined from the east by the B4032, the very bendy (but fun) road to Leighton Buzzard.

The A413 entering Buckingham

On through Winslow, over the railway closed to passengers in 1968 (this is the "Varsity Line" and plans to reopen it turn up quite often), and forward to Buckingham past Addington Manor on the left and then through Padbury village. The A413 now approaches the former county town, reaching a new ring road at a busy roundabout. Our road turns right and joins the A421 for half a mile before taking a left at the next roundabout to become the A413 again. Once over another roundabout and river bridge and to a roundabout on the A422, the A413 turns back into the town centre, before turning right to joining its old route and climbing up the hill out of the town. Those who know the town ignore the signs at the entry to Buckingham and simply go straight into the town from the ring road, past the University of Buckingham on the right, and down to the centre.

The road is now a fast-ish sweeping route to the A43 except for the parts through Maids Moreton (essentially a suburb of Buckingham), Akeley and Whittlebury. It joins the new, upgraded to dual carriageway, Oxford to Northampton road at a dumbbell junction about two miles north of Silverstone motor racing circuit (worth a detour, especially on a test or practice day). This junction only has north-facing slip roads, so the A413 doubles back south-south-westward along the old route of the A43 through Silverstone for around 4.5 km to meet a full-access junction for the A43 and an unclassified dual carriageway leading to the racing circuit.

Opening Dates

Year	Section	Notes
1959	Great Missenden Bypass	2.5 mile, 33 foot carriageway road, opened 26 October 1959. Cost £235,000.
1968	Chalfont St Peter Bypass	1.75 miles from Joiners Lane roundabout to just before the later M25 bridge. Buckinghamshire Advertiser of 26 July 1968 reported that it had recently opened. 100 feet wide with dual 24 feet carriageways. Forecast cost £0.6 million.
1987	Amersham Bypass	The 2.3 mile road from Shardeloes Roundabout to Stanley Roundabout was opened on 4 September 1987 by Wilfred Rooke, County Council Chairman. Contractor was ARC Construction Ltd., cost £6 million.
1997	Wendover Bypass	Buckinghamshire Examiner of 24 October 1997 reported that it had opened “this week”. Cost £7 million.