Great Central Main Line

The Great Central Main Line (GCML), also known as the London Extension of the Manchester, Sheffield and Lincolnshire Railway (MS&LR), is a former railway line in the United Kingdom. The line was opened in 1899 and built by the Great Central Railway running from Sheffield in the North of England, southwards through Nottingham and Leicester to Marylebone in London.

The GCML was the last main line railway to be built in Britain during the Victorian period. It was built by the railway entrepreneur Edward Watkin with the aim to run as a fast trunk route from the North and the East Midlands to London and the south of England. Initially not a financial success, it recovered under the leadership of Sam Fay. Although initially planned for long-distance passenger services, in practice the line's most important function became to carry goods traffic, notably coal.

In the 1960s, the line was considered by Dr Beeching as an unnecessary duplication of other lines that served the same places, especially the Midland Main Line and to a lesser extent the West Coast Main Line. Most of the route was closed between 1966 and 1969 under the Beeching axe.

Parts of the former main line have been preserved as the Great Central Railway between Leicester and Loughborough, and the Great Central Railway (Nottingham) between Loughborough South Junction and Ruddington's former GCR station site.

At the end of the 20th century and in the 21st century, the line has been subject to a range of proposals for its use and reuse.