On 1 April 1871 the section between Quainton Road and Wotton was formally opened by the Duke in a brief ceremony. At the time of its opening the line was unnamed, although it was referred to as "The Quainton Tramway" in internal correspondence. The extension from Wotton to Wood Siding was complete by 17 June 1871; the opening date of the northern branch to Kingswood is not recorded, but it was not yet fully open in February 1873. The London and North Western Railway immediately began to operate a dedicated service from Quainton Road, with three vans per week of milk collected from the Wotton estate shipped to Broad Street. Passengers were not carried, other than estate employees and people accompanying livestock.