The first trolleybus wiring erected was a training loop on Erleigh Road, which opened in early 1936. This loop was never used in public service, and was subsequently dismantled. Public service commenced on 18 July 1936, on a route replacing the tram route from Caversham Road to Whitley Street. In May 1939, the remaining tram routes from Oxford Road to Wokingham Road and London Road were converted to trolleybus operation, with a short extension from Wokingham Road to the Three Tuns, and a much longer extension from the Oxford Road through the centre of Tilehurst to the Bear Inn. The extended "main line", from the Three Tuns to the Bear, still exists today as bus route 17, the town's busiest and most frequent route, and the first to be designated a premier route.