|From:||Sible Hedingham (TL786326)|
|Length:||15.9 miles (25.6 km)|
|Meets:||A1017, A131, A12, A133, A134|
|Former Number(s):||A12, A132, A133 A135, A604|
|Route outline (key)|
It starts on the A1017 to the south of Sible Hedingham and zigzags southeast to Halstead, crossing the A131 via a short multiplex between mini-roundabouts either side of the church. It then follows the Colne Valley downstream. The river is crossed on the edge of Halstead and then again in Earls Colne. In Chappel the road goes under a viaduct on the Sudbury Branch Line, then the River Colne is crossed again in Fordstreet.
After going through Eight Ash Green the road crosses the Anglia Main Line to reach the A12 at J26, with a short section of dual-carriageway either side of the roundabout. The remainder of the route is mostly the old A12. A spur of the A133 bears off at a roundabout in Lexden and we continue through the suburbs of Colchester to end on a roundabout on the A134 in the town centre.
The A1124 was originally allocated in 1934 on completion of the Colchester Bypass to Greenstead Road in Colchester, running on the old route of the A133.
On 1st April 1936 (see 1935 Road numbering revision), it was extended over the western section of the A135 and eastern section of the A132 - effectively the old pre-bypass route of the A12 - up to where the bypass rejoined the original route at both ends. The remaining sections of the A132 and A135 became the A604.
In 1997, the A1124 was extended further along the old line of the A604 to the A1017. The old route through Colchester has also been downgraded following the rerouting of the A134 along the south side of the town.