Chiltern Main Line


The Chiltern Main Line is a railway line which links London and Birmingham on a route via High Wycombe, Bicester, Banbury, Leamington Spa and Solihull in England.
It is currently one of two main line railway routes between London and Birmingham; the other is the West Coast Main Line between London Euston and, which is the principal inter-city route between the two cities. A third main line, High Speed 2, is currently under construction.
The name Chiltern Line was invented as a marketing name for the line by Network SouthEast in 1985, with reference to the Chiltern Hills that the route passes through near its southern end. The route was originally part of the Great Western Railway's main line from London Paddington to Birmingham Snow Hill, and. Most main line services between London and Birmingham on this route were discontinued in 1967 after the West Coast Main Line was electrified, and Snow Hill station was closed.
Services were resumed between London and the reopened Snow Hill in 1993; however, they were routed into Marylebone, formerly the London terminus of the now-closed Great Central Main Line, instead of the historic terminus at Paddington.
Since the privatisation of British Rail in the 1990s, the main operator has been Chiltern Railways, which has continued to develop the route and services. In the early 2010s, the line [|underwent a major upgrade] which saw much of the line cleared for 100 mph running, resulting in significant reductions in journey times from 2013. The line is not electrified, although electrification is an aspiration.
The line forms part of the suburban rail networks in both cities. The majority of towns towards the London end of the route are prosperous suburbs or commuter-belt towns, such as Ruislip, Gerrards Cross and Beaconsfield; these have a journey time of 30 minutes or less to London Marylebone. In the West Midlands, it is one of the Snow Hill Lines. Commuter trains operated by West Midlands Trains run between Birmingham Snow Hill, and, also to Stratford-upon-Avon.

History

Early history and construction

What is now the Chiltern Main Line was built in three key phases by the Great Western Railway between 1852 and 1910:
  • The first phase was the Birmingham and Oxford Junction Railway opened in 1852. The route ran from to Birmingham Snow Hill; in 1854, it was extended to Wolverhampton Low Level and, connecting with other GWR lines, became the southern leg of a longer distance route to, and Birkenhead. It ran via the Great Western Main Line to and then via, and Leamington Spa. This route was circuitous and was longer between London and Birmingham than the rival London and North Western Railway's Euston-New Street route via, meaning that the GWR could not compete on journey times.
  • The second phase was completed in 1906. In order to create a more direct route, the GWR collaborated with the Great Central Railway to create a new railway known as the Great Western and Great Central Joint Railway between Northolt and Ashendon Junction via.
  • Thirdly, as a final development, the GWR opened the Bicester cut-off line in 1910; this was an connection between the Great Western and Great Central Joint Railway at Ashendon Junction, via, to Aynho Junction on the Birmingham line south of Banbury. This shortened the route between London and Birmingham by, compared to the original Oxford route, and reduced the fastest London-Birmingham journey times by 20 minutes. Most of the through trains were immediately transferred to the new route, although the original route via Oxford continued in use and is now known as the Cherwell Valley line.

    GWR era

Once the route between Birmingham and London was completed in 1852, the GWR introduced its first expresses between the two cities, timed at 2 hours 45 minutes, however this was soon revised to three hours, which matched the timings of the rival LNWR service. There was relatively little improvement for the rest of the 19th century, and three-hour expresses remained the standard timing of both companies until 1905, when the LNWR introduced new, more powerful Precursor Class locomotives, which allowed them to introduce two-hour expresses. The GWR could not compete with this, and it spurred the shortening of its route, as detailed above, which allowed them to introduce a matching timing of two hours once the works were completed in 1910.

Heyday, decline and rationalisation

During the heyday of the route, many prestigious trains ran from Paddington to the north-west of England, via the Joint Line; these reached Wolverhampton,,, Chester and Birkenhead Woodside. Various through services from Marylebone to the GCR network also ran via the Joint Line between London and Ashendon Junction.
At nationalisation in 1948, the line passed to the Western Region of British Railways, which continued to operate Paddington-Birmingham-Wolverhampton-Birkenhead fast trains through the 1950s in competition with the London Midland Region's from Euston via the West Coast Main Line.
The Paddington-Birmingham-Wolverhampton-Birkenhead fast service was increased sharply in frequency to up to 15 trains a day each way from the 1959–60 timetable to compensate for the withdrawal of most London Midlands Region trains during electrification of the WCML. For the same reason, the Chiltern line was used by many trains between Paddington and Birkenhead from 1965.
All local trains were diverted to Marylebone in 1963 and operated by four-car Class 115 diesel multiple units and the main-line platforms at Greenford, on the New North route between Old Oak Common and Northolt Junction, were closed.
After the GCR main line was closed between and in September 1966, some trains from the South Coast were diverted north of Banbury via the route. These became the forerunners of today's CrossCountry services between Birmingham and.
On 6 March 1967, after completion of the WCML electrification, express trains from Paddington to Birmingham/Wolverhampton/Birkenhead were discontinued under The Reshaping of British Railways. The route was downgraded to secondary status, with all but one of the main-line services between London and Birmingham diverted via Oxford. In 1968, the line between Princes Risborough and Aynho Junction was reduced to single track and only a basic two-hourly DMU service between Marylebone and Banbury remained to serve Bicester. Through lines were removed from most of those stations which had them, including Denham in 1965, Beaconsfield in 1973 and Gerrards Cross in 1989; the relief lines were lifted between Lapworth and Tyseley. The tunnel between Birmingham Moor Street and Snow Hill was closed on 2 March 1968. Local services from Leamington and Stratford terminated at Moor Street; the remaining services from Paddington and the South Coast were diverted into New Street. Snow Hill closed completely, along with most of the line to Wolverhampton, on 4 March 1972.
On 24 March 1974, the line from Marylebone to Banbury transferred from the Western Region to the London Midland Region; all stations between South Ruislip and Bicester were also transferred to LMR, giving LMR the responsibility of all passenger services out of Marylebone.
In 1977, the Parliamentary Select Committee on Nationalised Industries recommended considering electrification of more of the rail network and, by 1979, BR presented a range of options to electrify numerous routes by 2000. Some of these options included the Banbury–Birmingham section of the line, plus the Cherwell Valley Line and the Coventry to Leamington line. Under the 1979–90 Conservative governments that succeeded the 1976–79 Labour government, the proposals were not implemented.
The route was considered for partial closure between Marylebone and Northolt Junction in the early 1980s. All services would have run to Paddington, via the New North route; Marylebone station, and all lines leading to it, would have been closed and converted into a bus station. Services to and from Aylesbury would have been taken over by London Underground and run into Baker Street. However, these proposals proved impractical and Marylebone was formally reprieved in 1986 and the closure proposals rescinded.

Rejuvenation

With the sectorisation of British Rail in the mid-1980s, operations south of Banbury fell under the control of Network SouthEast in 1986, under the Thames & Chiltern sub-sector; this was split later into two constituent parts. In 1987, a new station was opened at Haddenham & Thame Parkway. Birmingham Snow Hill reopened in 1987, on a much smaller scale than the original, beneath a multi-storey car park; its tunnel was reinstated and new platforms added to the through lines at Moor Street, where the terminus was taken out of use. Leamington/Stratford services were diverted to Snow Hill.
The opening of the extension of the parallel M40 motorway from Oxford to Birmingham in 1991 spawned development in towns along the northern section of the route, notably Bicester, Banbury, Leamington Spa and Warwick. This generated additional patronage for train services in the corridor.
Between 1988 and 1992, British Rail used the Chiltern Line as a test bed for total route modernisation; this included resignalling from Marylebone to Aynho Junction, and both Marylebone to Aylesbury routes, from the new Marylebone Integrated Control Centre, with full Automatic Train Protection provided. The track was renewed and Marylebone was refurbished. Much of this work was funded by selling part of Marylebone for development, which meant that the station lost two of its platforms; the central cab road at Marylebone was removed and two replacement platforms inserted in its place.
New Turbo trains were introduced in 1991, replacing the ageing 1960s diesels. These improved passenger comfort and enabled journey times to be reduced; frequencies were increased, with an hourly stopping service to/from High Wycombe and hourly semi-fast service to/from Banbury. In 1993, Marylebone-Banbury services were extended to Snow Hill, calling at Leamington Spa, Warwick, Solihull and Moor Street, initially on a two-hourly frequency; these were increased to hourly in the following year. In 1995, the Jewellery Line was reopened, to allow Worcester line services to be diverted from New Street to Snow Hill; this resulted in some of Chiltern's weekday peak-period services to be extended beyond Snow Hill, first to Stourbridge Junction and then to Kidderminster.