43183 emerges from Ardley Tunnel on 15 October 2010 with the 1Z11 08:03 Paddington to Banbury First Great Western proving run, in connection with planned diversions over the Christmas period. It would later work the 1Z12 09:57 Banbury to Westbury, 1Z13 12:10 Westbury to Waterloo, and finally the 1Z14 15:10 Waterloo to Paddington. HSTs are exceedingly rare on the Chiltern Line, and I thought I would revisit this location, as I used it for the previous visit of a HST railtour in 1994. The track has been doubled since then! For some unexplained reason, even though there was hardly a breath of wind, just before the train appeared, a flurry of hawthorn leaves starting drifting across the tunnel mouth.