Although the Fairford Branch Line started at Yarnton Junction, most journeys would not have started at Yarnton, but rather at Oxford, from what at the time was the Great Western Railway station. Fairford trains would have travelled north out of the station, taking the Cotswold Line at Wolvercote Junction, before soon arriving at Yarnton.

22xx 0-6-0 2221 stands in the down bay at Oxford, with the Cripley Road sidings on the right. Although undated, this picture was clearly taken in June 1962, as the locomotive carries a chalked inscription 'The Fairford Flyer', and although illegible in this particular picture, the wording underneath the loco's number mentions Beeching.
Martin Loader Collection

74xx 0-6-0PT 7412 waits in the up bay at Oxford with a train from Fairford in 1958. Oxford station had, and even after recent rebuilding, still has only two through platform faces, admittedly with the addition of two through roads. This limited capacity was a severe handicap, and in steam days on busy summer Saturdays, trains were often queued up block to block as far back as Kennington Junction. Passengers on down trains were left contemplating Osney graveyard as their train stood on 'Cemetery Curve' awaiting their turn at the platform! The train on the left in this view is a down service to either Worcester or Birmingham. Note the gas tanks on the right and Oxford North signal box in the distance. 
Martin Loader Collection

A superb signal gantry used to span the tracks at the north end of Oxford station in the 1960s. This picture, which also includes Oxford Station North Signal Box, was taken after the Fairford Branch Line had closed. The Fairford bay tracks crossed the bridge in the foreground, which is here being used as an access road to the nearby Oxford (81F) depot. Both the signal box and the gantry were removed after the 1973 installation of colour light signalling in the area. The other unmistakable landmark in this picture is the Italianate church of St Barnabas, in Jericho.
Stanley C. Jenkins

57xx 0-6-0PT 9654 heads north from Oxford in the 1950s. The train is approaching Walton Well Road, the first road overbridge to the north of the station. Oxford locomotive depot was sitiated just ff to the right of the picture.
R. H. G. Simpson

57xx 0-6-0PT 9653 races along the main line at Wolvercote with the 16:26 Oxford to Fairford train on the final day of passenger operations - 16 June 1962. This train is also pictured on the Brize Norton & Bampton page. The train is running on the down main. The down goods loop (opened in 1942) can be seen on the extreme right, with a ditch between it and the other running lines. This has long since been removed. The up goods loop (still extant) is on the extreme left, with a junction trailing into the up main at this point. 
Colour Rail