The Midland Main Line is a major railway line in England from London to Sheffield in the North of England. The line is under the Network Rail description of Route 19; it comprises the lines from London's St. Pancras station via Leicester, Derby/Nottingham and Chesterfield in the East Midlands. Express passenger services on the line are operated by East Midlands Trains. The section between St Pancras and Bedford is electrified and forms the northern half of Thameslink (mainly operated by Thameslink and Great Northern), with a fast service to Brighton and other suburban services.