The railway had declined considerably during
World War I, and following the
Railways Act 1921 most of the main line railways of Great Britain were "grouped" into one or other of four new large companies. The Great Northern Railway was a constituent of the
London and North Eastern Railway (LNER). The industrial and colliery activity in the area served by the line declined, and road competition sharpened considerably, seriously reducing the viability of the line. The Midland Railway was a constituent of the new
London, Midland and Scottish Railway (LMS), so that the competition continued. In 1939 the wartime emergency was considered to require a drastic reduction of the passenger services between Derby and Burton. In fact bus competition had already resulted in reduction of the service to eight trains in each direction compared with eleven in 1922. From 4 December 1939 the passenger service west of Derby was discontinued when both services were completely withdrawn and
Mickleover,
Etwall,
Egginton Junction (LNER platforms only), and the stations between
Uttoxeter and Stafford closed to passengers. The service between Derby and Nottingham was also substantially reduced, comprising nine eastbound trains (10 on Saturdays) and 10 westbound (11 on Saturdays) in May 1941, with a Sunday service of three to Grantham and two return. During
World War II a military ordnance depot was opened at West Hallam in 1941, with an extensive internal siding network. Meanwhile, passenger business sank further, and the passenger service between Derby and Nottingham was discontinued on 7 September 1964. On 6 May 1968 the Derbyshire Extension was closed to all commercial traffic between Ilkeston (Stanton Junction), Egginton Junction, and Burton (Hawkins Lane), and the remainder of the ex-GNR system north and west of Nottingham closed too within the following few weeks. The track from Derby Friargate to Egginton Junction was retained for experimental use by the British Railways
Railway Technical Centre, based in Derby. This was cut back to the shorter section between Mickleover and Egginton after 26 November 1971. ==Locations==