The Chiltern Main Line is an inter-urban, regional and commuter railway, part of the
British railway system. It links
Moor Street and
Snow Hill), the United Kingdom's two largest cities, by a 112-mile (180 km) route via
It is one of two main line railway routes between London and Birmingham, the other being the
West Coast Main Line between
London Euston and
Birmingham New Street, which is the principal
InterCity route between the two cities.
The name Chiltern Line was invented as a marketing name for the line by
Network SouthEast in 1985,
 in reference to the
Chiltern Hills which 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.
Wolverhampton Low Level and
Birkenhead Woodside. 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.
privatisation of British Rail in the 1990s, the main
operator has been
Chiltern Railways who have continued to develop the route and services. The line has
undergone a major upgrade which has seen much of the line cleared for 100 mph (160km/h) running, resulting 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
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
London Midland run between
Birmingham Snow Hill,