|Distance:||35.1 miles (56.5 km)|
|Meets:||A45, A14, A427, A1(M), A1139, A1, A1260, A15, A1129, A1139, A141|
|Former Number(s):||B663, B665, B1093, B1097|
|Old route now:||A45, B1092|
|Route outline (key)|
Thrapston - Peterborough
The road follows the lush valley of the Nene, skirting Barnwell, seat of the Dukes of Gloucester and once the haunt of the Large Blue butterfly. Oundle, with its narrow streets, is now bypassed, so the A427 meets us to the north of the town. At Elton Hall the B671 leaves for Wansford, and we are now on a new section of road that joins the top end of the A1(M). The road ahead - and the obvious route for through traffic - is the A1139 but the A605 multiplexes north along the A1 as far as the next junction.
Peterborough - Guyhirn
Although Peterborough has altered beyond recognition since classification in 1922 the A605 still follows its original route into town. Leaving the A1 at Alwalton the road heads east past the East of England Showground and a number of roundabouts to cross the A1260 western inner bypass at a north-facing GSJ, Peterborough J32. A mile or so further on the road goes under the East Coast Main Line to meet the A15 at traffic lights to the south of the city centre. There's a short multiplex past the football stadium, then the A605 heads southeastwards to go under the A1139 eastern bypass.
Now things get even more complicated. The B1092 through Stanground is obviously the old route of the A605 - but the road now follows the A1139 westwards, crossing it twice at adjacent GSJs (J4 and J3A) before heading back east to bypass Stanground; only the western half of the bypass is dualled.
The road rejoins its pre-bypass route and heads east into Whittlesey, where Clement Freud was once the MP. From here on the fens dominate, and roads are very straight or beset with right-angled corners. After Eastrea and Coates the old road (which was Class II) used to wiggle off to March, but the A605 follows a "new" stretch of road parallel to Moreton Leam and the realigned River Nene, to join the A141 in, frankly, the middle of nowhere. Actually, Guyhirn is a mile and a half to the north, and March three miles to the south.
The A605 is described in the 1922 Road Lists as Thrapston - Oundle - Peterborough, running between the old A604 and the A15. The road was then extended at both ends, to Higham Ferrers on the A6 and, later, eastward to the A141 (although it ended arbitrarily in the centre of Whittlesey for a few years). Now it's contracted somewhat again at its western end due to the rerouting of the A45, and currently begins at a GSJ on the A14 east of Thrapston.
The western, primary, half of the A605 has been heavily upgraded and bypassed. For example, the road once went through Oundle and there was originally no multiplex along the A1.