Snaefell Mountain Course o Mountain Course ("Ruta de la montaña Snaefel" o "Ruta de la montaña")Isle of Man Centenary TT - ACU/MMCC Official Race Guide pp67 Isle of Man Department of Tourism and Leisure (2007) Mannin Media Group Ltd es un circuito en carretera usado para el TT Isla de Man y el Manx Grand Prix, que se vienen llevando a cabo en la Isla de Man desde 1911 y 1923 respectivamente. La competición se realiza en carreteras públicas cerradas al tráfico para este propósito, según un acta del Tynwald (el nombre del parlamento manés). Es el circuito de motociclismo, que todavía está en uso, más antiguo del planeta.
El circuito tiene un recorrido de 60,73 km,Official TT Guide 1992 pp 45 Mannin Media Publication/Isle of Man Department of Tourism y su línea de salida se encuentra en la carretera A2, llamada Glencrutchery Road, en la ciudad de Douglas. El circuito está basado en un número de carreteras públicas de la isla, incluyendo la A2 de Douglas a Ramsey, la carretera A1 de Douglas a Peel, la carretera A3 desde Castletown a Ramsey y la carretera principal A18, que escala el monte Snaefell. El punto más alto del circuito se sitúa en esta última carretera, entre Bungalow y Hailwood's Height, con una cota de 422 metros sobre el nivel del mar ).
Historia
Las competiciones de motor se iniciaron en la Isla de Man hacia 1904 con la carrera Trial Gordon Bennett y estaba originalmente concebida exclusivamente para automóviles de turismo. Tras el Motor Car Act 1903, y que este legalizara un límite de velocidad de 20 millas por hora para los automóviles en el Reino Unido, el Secretario del Automobile Car Club of Britain and Ireland solicitó a las autoridades de la Isla de Man un permiso para competir por las carreteras públicas.Island Racer 2004 pp 112-113 Mortons Media Group Ltd ISSN 1743-5838 La ley del Tynwald The Highways (Light Locomotives) Act 1904 dio permiso en la Isla de Man para que se llevara a cabo la carrera Gordon Bennett trial de 1904 en el circuito Highroads Course de 83,93 km.The Statutes of the Isle of Man Vol VII from 1896 to 1905 pp569 Edited by C.T.W Hughes-Games Brown and Sons Ltd
Para la edición de la misma carrera del año 1905 se decidió que también participaran motocicletas el día posterior, por un equipo que iría a representar a Gran Bretaña en las carreras de la Copa Internacional de Motocicletas. La inhabilidad de los competidores en motocicleta para escalar la carretera A18 forzó a los organizadores de la carrera a usar una sección de unos 40 km de longitud del circuito del Gordon Bennett Trial. Por esta razón, la edición 1907 del TT Isla de Man usó el St. John's Short Course, de 25,49 km. La edición de 1906 para automóviles se realizó en el Highroad Course, que se redujo de 83,879 km a unos 65 km. El trazado se volvió a acortar en 1908 para automóviles, hasta dejarlo en apenas 60,35 km debido a la supresión de los enlaces de Peel y Sandygate, y se transformó así en el conocido como Four Inch Course ("Ruta de 4 pulgadas").TT Pioneers - Early Car Racing in the Isle of Man pp 103-104 Robert Kelly, Mercury Asset Management (1996)(1st Edition) The Manx Experience, The Alden Press ISBN No 1 873120 61 3 El nombre de la ruta deriva de las normativas adoptadas en 1908 para el Tourist Trophy por el Royal Automobile Club, que limitaba el diámetro de los cilindros del motor de los coches participantes a 4 pulgada, el equivalente a 102 mm. La "Ruta de 4 pulgadas" fue adoptada por el Auto-Cycle Club para las carreras de 1911. La "Ruta de 4 pulgadas" por tanto, se convirtió en el Snaefell Mountain Course o Mountain Course ("Ruta de la montaña Snaefel" o "Ruta de la montaña") cuando se usaba para competiciones motociclistas.TT Pioneers - Early Car Racing in the Isle of Man pp 103-104 Robert Kelly, Mercury Asset Management (1996)(1st Edition) The Manx Experience, The Alden Press ISBN No 1 873120 61 3
Cambios al recorrido 1920-1939 thumb|right|230px|Brandywell TT Race Marshal Shelter and Weather Station on the A18 Mountain Road/B10 Sartfield Road looking north towards Snaefell Mountain and North Barrule
Para las carreras de 1920, se hicieron cambios a la ruta de la montaña, para que los competidores dieran vuelta a la izquierda en Cronk-ny-Mona y siguieran el curso de carretera de la montaña primaria A18 hacia el puente Governor's Bridge con una nueva meta en Glencrutchery Road lo que alargó la ruta desde la longitud que tenía antes de la World War I length of to . More changes to the course followed in 1923 with the adoption of a private road between Parliament Square and May Hill in Ramsey. The course had previously had negotiated the A2 Albert Road and Tower Road in Ramsey and the new course length was now . The official course distance for the Snaefell Mountain Course was amended in 1938 to which is the current course length.Official TT Guide 1992 pp 45 edited by Norrie White Isle of Man Department of Tourism (1992) Mannin Media Ltd
Para las carreras de 1934 Isle of Man TT major alterations to the Mountain Course were carried out which included the removal of the East Snaefell Mountain sheep-gate.Isle of Man Examiner dated 31st May 1934 This was followed by the removal of the hump-backed bridge at Ballig and the road work was completed for the Manx Grand Prix in September 1935. Road widening occurred on the Mountain Course at the Highlander, Laurel Bank, Glen Helen (between the Old Quarry and Brew's Restaurant) and at Brandywell with the removal of the Beinn-y-Phott sheep-gate for the 1935 Isle of Man TT Races.Isle of Man Weekly Times dated 25th May 1935 Road Improvements occurred at the 26th Milestone, Greeba Bridge and on the Sulby Straight for the 1938 Isle of Man TT Races. Further road widening and landscaping occurred at the Water Works Corner and road widening between the Gooseneck and the 26th Milestone for the 1939 Isle of Man TT Races.Isle of Man Weekly Times pp4 dated 13th May 1939 A memorial to Jimmie Guthrie was built in 1939 at the The Cutting at a cost of £1,500.Isle of Man Weekly Times pp18 dated 17th June 1939
Cambios a la ruta en el periodo 1947-1999 Major road widening occurred on the Snaefell Mountain course at the 33rd Milestone, including the removal of fence posts at road level and the removal of a section of a grass bank before the start of the 1947 Isle of Man TT Races.Isle of Man Weekly Times dated 12th May 1947 Changes to the Mountain Course occurred for the 1953 Isle of Man TT Races including road widening at Bedstead Corner, elevation works at Signpost Corner and Cronk-ny-Mona and the widening of the corner at Gorse Lea.Isle of Man Weekly Times pp7 dated 25th April 1953 Before the commencement of racing for the 1953 Manx Grand Prix, the cottage at Appledene Corner was demolished between the 6th and 7th Milestone road-side marker on the primary A1 Douglas to Peel road on the Mountain Course.Isle of Man Examiner pp12 dated 14th August 1953 Further changes occurred to the Mountain Course to facilitate racing on the Clypse Course and during the winter of 1953/54 road widening occurred on the primary A18 Mountain Road at Creg-ny-Baa, Signpost Corner, Cronk-ny-Mona and at the approach to Governor's Bridge.Isle of Man Examiner pp12 dated 5th January 1954 The approach to the Quarterbridge on the primary A2 Douglas to Peel road was widened and re-profiled and the jumps at the Highlander and adjacent to Ballagarraghyn Cottages were removed for the 1954 Isle of Man TT Races.TT 100 - The Authorised History of the Isle of Man Tourist Trophy Racing by Mick Duckworth pp111 (2007)(1st Edition) Lily Publications ISBN 1-8996067-4 Other major course alterations for the 1954 Isle of Man TT Races included road widening at Appledene, Handley's Corner, Barregarrow, Rhencullen, Ballaugh Bridge, Ginger Hall (Sulby) and Kerrowmoar.Isle of Man Examiner pp6 dated 28th May 1954 During the winter of 1957/58 the hotel at the Bungalow tram-crossing was removed on the Mountain Section of the course.Isle of Man Examiner pp1 dated 10 April 1958TT 100 - The Authorised History of the Isle of Man Tourist Trophy Racing by Mick Duckworth pp29 (2007)(1st Edition) Lily Publications ISBN 1-89960-67-4
Durante los 1960s further road-widening occurred at Ballig and also at Greeba Bridge on the primary A1 Douglas to Peel road. In 1963 a roundabout was added to the road junction at the Quarterbridge.Isle of Man Examiner pp5 dated 6th June 1963 The winter of 1970/1971 road-widening occurred on the A18 Mountain Road at Verandah by cutting into the hillside.Isle of Man Weekly Times pp1 dated 6th January 1971 The winter of 1975/76 road-widening and landscaping occurred at Snugbrough on the primary A2 road at the 2nd Milestone.TT 100 The Official Authorised History of Isle of Man Tourist Tophy Racing page 21 by Mick Duckworth Editor Miles Coswell (2007)(1st Edition) Lily Publications Ltd ISBN 1 899602 67 4 The winter of 1986 further re-profiling occurred at the Quarterbridge road junction with a new road traffic system including two new mini-roundabouts, the removal of a traffic island and trees. Road re-profiling and widening occurred at Quarry Bends during the winter of 1987. During the winter months of 1991/1992 the A18 Mountain Road was closed for repair work to the road foundation between the 26th Milestone and the Mountain Box and also between the Windy Corner and Keppel Gate.Official Isle of Man TT Programme 1992 pp 45 edited by Norrie White Isle of Man Department of Tourism (1992) Mannin Media Ltd
Cambios a la ruta desde el 2000 thumb|left|200px|Governor's Bridge road junction between the A18 Bemahauge Road and the A2 Governor's Road.