Wantage sits at the crossing of the B4507 valley road , the A417 Reading to Cirencester road and the A338 Hungerford ( and junction 14 of the M4 motorway ) to Oxford road . Wantage is at the crossing of the B4507 valley road , the A417 road between Reading and Cirencester and the A338 road between Hungerford ( and junction 14 of the M4 motorway ) and Oxford .