One of the original 1871 Aveling and Porter locomotives used by the line
On 23 September 1868 the small Aylesbury and Buckingham Railway (A&BR) opened, linking the Great Western Railway's station at Aylesbury to the London and North Western Railway's Oxford to Bletchley line at Verney Junction. On 1 September 1894 London's Metropolitan Railway (MR) reached Aylesbury, and shortly afterwards connected to the A&BR line, with local MR services running to Verney Junction from 1 April 1894. Through trains from the MR's London terminus at Baker Street commenced on 1 January 1897.
The Duke of Buckingham had long had an interest in railways, and had served as Chairman of the London and North Western Railway from 1852 to 1861. In the early 1870s he decided to build a light railway to carry freight from his estates in Buckinghamshire to the A&BR's line at Quainton Road. Because the proposed line ran on land owned by the Duke of Buckingham and by the Winwood Charity Trust, who consented to its construction, the line did not need Parliamentary approval and construction could begin immediately.
The first stage of the line, known as the Wotton Tramway, was a 4-mile (6.4 km) line from Quainton Road via Wotton to a coal siding at Kingswood, and opened on 1 April 1871. Intended for use by horse trams, the line was built with longitudinal sleepers to avoid horses tripping on the sleepers. In November 1871 the tramway was extended to Wood Siding, in a surviving fragment of Bernwood Forest 1 1⁄2 miles (2.4 km) from the town of Brill and 1,500 yards (1,400 m) from the nearest settlement at Dorton.
Lobbying from residents and businesses in Brill for the introduction of passenger services on the line led to a 1,840-yard (1,680 m) further extension from Wood Siding to Brill railway station, at the foot of
Brill Hill 3⁄4 of a mile (1.2 km) from the hilltop town of Brill itself, in mid-1872. Two mixed trains ran each day in each direction, and the line was renamed the Brill Tramway. The Duke bought two Aveling and Porter traction engines modified to work as locomotives for the line, each with a top speed of 8 miles per hour (13 km/h), although a speed limit of 5 miles per hour (8 km/h) was enforced.
The Duke of Buckingham, founder of the Brill Tramway
The Duke died in 1889, and in 1894 the trustees of his estate set up the Oxford & Aylesbury Tramroad Company (O&ATC) with the intention of extending the line from Brill to Oxford. Rail services from London to Oxford were very poor at this time; despite being an extremely roundabout route, had the connection from Quainton Road to Oxford been built it would have been the shortest route between Oxford and the City of London. The Metropolitan Railway leased the Brill Tramway from 1 December 1899, and from then on the MR (the Metropolitan line of the London Underground from July 1933) operated all services on the line. Throughout the operation of the Brill Tramway the track and stations remained in the ownership of the Oxford & Aylesbury Tramroad Company; the MR had an option to purchase the line outright, but it was never taken up.