With a railway near the border of Wotton House estate, the 3rd Duke decided to build a small-scale agricultural railway to connect the estate to the railway. His intended route ran on his own land other than a small stretch west of the Aylesbury and Buckingham line. This land was owned by the Winwood Charity Trust, an operator of
almshouses in Quainton of which the Duke was a trustee. The Duke agreed to pay an annual rent of £12 (about £ in ), in return for permission to run trains. With the consent of the Winwood Charity the route did not require Parliamentary approval, and construction could begin immediately. The Duke envisaged a
tramway west from
Quainton Road railway station across his Wotton estate. The line was intended for transport of construction materials and agricultural produce and not for passengers. It would not have a junction with the Aylesbury and Buckingham railway, but would have its own station at Quainton Road at a right angle to the A&B's line. A
turntable at the end of the tramway would link to a spur from the A&B's line. The line was to run roughly southwest from Quainton Road to
Wotton near Wotton Underwood. Just west of the station at Wotton the line split. One section would run west to
Wood Siding near Brill. A short stub called Church Siding would run northwest into Wotton Underwood itself, terminating near the parish church, and a siding would run north to a coal siding near
Kingswood. The branch to Kingswood was routed to pass a pond, to allow the horses working the line to drink.
Ralph Augustus Jones was appointed Manager of the project, and construction began on 8 September 1870. Twenty labourers from the Wotton estate who would otherwise have been unemployed following harvest were employed six days a week to build the line, each paid 11 s per week. They carried out all the construction except laying the track, which was done by the specialists, Lawford & Houghton. The line was built using the cheapest materials and winding around hills to avoid expensive earthworks. The ballast was a mix of burnt clay and ash. The stations were crude earth banks high, held in place by wooden planks. As the Duke intended that the line be worked only by
horse-drawn carriages, the line was built with
longitudinal sleepers to reduce the risk of horses tripping. A diameter turntable was installed at Quainton Road to link the tramway to the Aylesbury and Buckingham Railway.
Opening On 1 April 1871, the section between Quainton Road and Wotton was formally opened by the Duke of Buckingham in a ceremony in which coal from the first goods wagon to arrive at Wotton was distributed to the poor. At its opening the line was unnamed, but 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 fully open in February 1873. The London and North Western Railway began a dedicated service from Quainton Road, with three vans a week of milk collected from the Wotton estate shipped to the London terminus at
Broad Street. The only passengers were estate employees and people accompanying livestock. The Duke and Jones intended to run no more than one train on each section of the line so the line was not built with
passing loops or signalling. When more than one horse-drawn train or locomotive was in operation, the Tramway operated a
token system using colour-coded staffs to ensure only one train could be on a section. Drivers between Quainton Road and Wotton carried a blue staff, those west of Wotton and the Kingswood siding a red staff. On 26 August 1871, an excursion ran from Wood Siding to London hauled by the
Great Western Railway (GWR). It carried around 150 people, for a total of passenger fares (with each child counted as half an adult), and was drawn by horses between Wood Siding and Quainton Road and by locomotive from Quainton Road to Aylesbury where the carriages were attached to the 7.30 am GWR service via Princes Risborough to London, arriving at 10.00 am. The experiment was not a success. Sharp overhanging branches posed a danger to passengers and had to be cut back in the week before the excursion. The day was wet and ticket sales were lower than expected. The return from London to Quainton Road was delayed in
Slough, and the excursion arrived back at Wood Siding at 2.00 am. {{Quote box|width=26em|salign=right|quote=This wet weather has considerably affected the incline just below the Lodge. The horses' feet sunk in very deep and they have been down once or twice—I do not think your Grace would wish them to pass over it again until something has been done. Some burnt ballast put down would make the footing firmer. On Monday three separate trucks ran off the line on the incline, but the road has since been firmed in. The surveyors designing the line had worked on the assumption that the wagons would have a load on each wheel of and had designed the line accordingly. As it turned out, the four-wheeled wagons used had an average weight of and each carried of goods, meaning this limit was regularly exceeded. The coal wagons used on the line weighed each and carried of coal, meaning a load on each wheel of . As well as damaging the track the loads strained the horses, and soon the line began to suffer with
derailments, particularly in wet weather. On 20 October 1871 Jones wrote to the Duke that "The traffic is now becoming so heavy that I would, most respectfully, venture to ask your Grace to consider the subject as to whether an Engine would not be the least expensive and most efficient power to work it."
Extension to Brill and conversion to steam In late 1871, residents of Brill petitioned the Duke to extend the route to Brill and open a passenger service. The Duke agreed; it is likely he had already planned passenger services to Brill, as correspondence from early 1871 mentions passenger facilities at "the Brill terminus". In January 1872 a scheduled passenger timetable was published and the line was named the "Wotton Tramway". (Officially called the "Wotton Tramway", it was commonly known as the "Brill Tramway" from the time of its conversion to passenger use.) The new terminus of
Brill railway station, at the foot of Brill Hill approximately north of the town, opened in March 1872. It was now a passenger railway, but goods traffic continued to be the primary purpose of the line. The line was heavily used to ship bricks from the brickworks around Brill, and cattle and milk from farms on the Wotton estate. By 1875 the line was carrying around of milk each year. The inbound delivery of
linseed cake to the dairy farms and of coal to the area's buildings were also important. The line began to carry manure from London to the area's farms, carrying in 1872. The tramway also opened a
cartage business to handle the onward shipment of goods and parcels unloaded at Brill and Wotton stations. With horses unable to cope, Jones and the Duke decided to convert at least part of the railway for
locomotives. The lightly laid track with longitudinal sleepers limited them to , and it was thus necessary to use the lightest locomotives possible. Two
traction engines converted for railway use were bought from
Aveling and Porter for £398 (about £ in ) each. They were chosen for weight and reliability, and had a top speed on the level of . They took 95–98 minutes between Brill and Quainton Road, an average of . With an unusual configuration in which a flywheel drove chains which in turn drove the wheels, the locomotives were noisy and were nicknamed "Old Chainey" by locals. The first of the new locomotives, given serial number 807 by Aveling and Porter and numbered 1 by the Tramway, was delivered to Wotton station on 27 January 1872. On the day of its delivery, the now-redundant horses had been sent away. Nobody at Wotton could operate the locomotive so a horse had to be hired from Aylesbury until the driver arrived. After the delivery of the second locomotive on 7 September 1872, all passenger services were drawn by locomotive except on Thursdays, when locomotives were replaced by horses to allow for maintenance. The line carried 104 passengers in January 1872, rising to 224 in April, and 456 in August 1872. With steam came the need for water. Plans to dig a well near Wotton came to nothing, and the Duke's expedient of drawing water from a pond near Quainton Road did not impress the pond's owner. By March 1872 Jones recorded that "The party to whom the pond near the Quainton Station belongs is making complaints about our having water and I expect he will be using force to prevent our getting any". A wooden water tower was built at Brill station, and a large water tower known as the Black Tank was built in the fork of the main line and Church Siding. The engines proved adequate but slow. On 6 February 1872, Jones timed one as taking 41 minutes to travel roughly from Quainton Road to Wotton hauling 42 tons (43 t). They were low-powered, and when pulling a heavy load their front wheels would lift off the track. The Duke's cost-cutting led to poor maintenance of track and equipment, and the service was often interrupted by derailments and accidents. In 1876, the Aylesbury and Buckingham Railway raised its prices for coal haulage. All coal hauled on the Tramway needed to pass along the A&BR from Verney Junction or Aylesbury and Jones had to raise prices to cover the surcharge or keep prices stable despite the loss of profits. Road-hauled coal from
Bicester was already undercutting the Tramway and the unreliable engines had given the Tramway a poor reputation. Jones kept prices fixed and absorbed the increased costs, wrecking the Tramway's already declining business. In 1873, the 3rd Duke attempted to have the Wotton Tramway recognised as a railway, and
William Yolland inspected the line in April 1873. The
Railway Regulation Act 1844 defined minimum standards of travel, one of which was that the trains travel at an average of , which the Aveling and Porter locomotives could not manage. None of the stopping places had adequate station buildings, and the line had no signals. Yolland permitted the line to continue as a tramway, but refused to recognise it as a railway. ==Improvement and diversification==