|Location Map ( geo)|
|Distance:||4.7 miles (7.6 km)|
|Former Number(s):||A4130, B4016|
|Route outline (key)|
It starts at the Chilton Junction with the A34 and A4185 and proceeds north east along Hagbourne Hill, to meet the A417 at a roundabout on the outskirts of West Hagbourne. There is then a short multiplex with the A417 until another roundabout immediately before the bridge over the A34 where the B4493 turns right onto a new road opened in 2018 to bypass Harwell village. At the end of the link road is another roundabout where the road meets its original self, with the section through Harwell (once the A4130) now unclassified.
The road merges into the suburbs of Didcot fairly soon and we enter town along Wantage Road. Presently a roundabout is reached. The town centre lies ahead but we turn left towards the station. After following Foxhall Road a further roundabout is reached where the station is to the right. We turn left and follow the road parallel to the Great Western Main Line to the next roundabout, where we end on the A4130.
Originally Foxhall Road was the B4016 and the rest of the route was part of the B4007. The latter was renumbered A4130 in the late 1920s and it seems likely that the B4493 came into existence around the same time when the B4016 number was reused nearby for a more significant route. When the A4130 gained its present route in the late 1980s the B4493 was extended in both directions giving it the majority of its current route.
In 2016 work began on improving Hagbourne Hill and building the Harwell Link Road, to improve traffic flow from the new housing developments being built in Didcot. When this was complete, the section between Chilton and Harwell was classified as an extension of the B4493.