The A418 road is a main trunk road in Buckinghamshire and Oxfordshire, England. It begins at a roundabout with the A4146 just north of Ascott, near Leighton Buzzard. It then runs south as a single carriageway through Wing to Aylesbury. This stretch is proposed for a dual carriageway bypass. After diving through Aylesbury the road runs past Aylesbury College before heading out into Stone. From here it runs past Haddenham to the M40 near Thame.