Signal box, 1893, by Saxby & Farmer for the South Eastern Railway.

Wye Signal Box, an 1893 Saxby & Farmer Type 12 signal box, is not designated for the following principal reasons: * Degree of intactness: while Wye is reasonably intact except for the removal of its staircase and the addition of a small later porch, there are better surviving examples of this design type at Rye and Wateringbury; * Survival of operating equipment: although it retains an 1888 Duplex lever frame other Type 12 signal boxes do also, including Wateringbury which additionally retains a number of block instruments; * Group Value: Wye does not group with any listed railway structures. Both Wateringbury and Rye group with listed railway stations and Wateringbury additionally groups with a listed goods shed.

From the 1840s, huts or cabins were provided for men operating railway signals. These were often located on raised platforms containing levers to operate the signals and in the early 1860s, the fully glazed signal box, initially raised high on stilts to give a good view down the line, emerged. The interlocking of signals and points, perhaps the most important single advance in rail safety, patented by John Saxby in 1856, was the final step in the evolution of railway signalling into a form recognisable today. Signal boxes were built to a great variety of different designs and sizes to meet traffic needs by signalling contractors and the railway companies themselves.

Signal box numbers peaked at around 12,000-13,000 for Great Britain just prior to the First World War and successive economies in working led to large reductions in their numbers from the 1920s onwards. British Railways inherited around 10,000 in 1948 and numbers dwindled rapidly to about 4,000 by 1970. In 2012, about 750 remained in use; it is anticipated that most will be rendered redundant over the next decade.

Saxby & Farmer moved away from hipped roof designs in the mid 1880s to gabled boxes and the Type 12 design was built in some numbers for the South Eastern Railway and the London, Chatham & Dover Railway between 1890 and 1894.

Wye Signal Box was built in 1893 and retains its frame of 1888 Duplex pattern. It closed in 2003 but the box has been retained. The external staircase was removed at some time after English Heritage's site visit on 02/05/2013 but before 03/07/2013.

Built in 1893 for the South Eastern Railway. The contractors were Saxby & Farmer and it is an example of their Type 12 signal box.

MATERIALS: lower floor brown brick in Flemish bond with a projecting plinth, the first floor is timber-framed, clad in weatherboarding. Gabled slate roof. The external wooden staircase was removed in 2013.

PLAN: two storeys with operating floor over locking floor. Three bays long by three bays wide, originally with a staircase at the south-west end.

EXTERIOR: north-west side facing the track has three six-pane sliding sash windows to the operating room and an access balcony with cast iron brackets. The cambered locking room window survives. The gable end has carved bargeboards and there are two four-pane windows, a half-glazed door and small later porch. The locking room has a panelled door. The north-east end has similar bargeboards, three four-pane windows and a continuation of the access balcony.

INTERIOR: the operating room retains a 24 lever 1888 Duplex lever frame. The locking room could not be accessed.