Sheffield–Lincoln line
The Sheffield–Lincoln line is a railway line in England. It runs from Sheffield to Lincoln via Worksop, Retford and Gainsborough Lea Road. The route comprises the main line of the former Manchester, Sheffield and Lincolnshire Railway (MS&LR), to Gainsborough Trent Junction, where it then follows the former Great Northern and Great Eastern Joint Railway (GNGEJR) to Lincoln Central. The former MS&LR main line continues from Trent Junction to Wrawby Junction, Barnetby, much of it now single line, where it then runs to Cleethorpes. Routes. Current services. The line comprises two passenger routes: the main line route  from Sheffield to Lincoln and a branch line route running from Sheffield to Cleethorpes, using the Brigg branch line from Gainsborough Trent Junction. North of Gainsborough Central the Brigg branch line primarily carries freight trains to/from the Port of Immingham. Main line route. The route largely follows the former "MS&LR" main line, until Trent Junction, Gainsborough where it goes on to follow the former "GNGEJR" line to Lincoln. An hourly service provided by Northern runs along this route. Additional services provided by East Midlands Railway serve the section between Lincoln and Gainsborough Lea Road en route to Doncaster. Brigg  branch line route. This route follows the former MS&LR main line to Cleethorpes. On weekdays and Saturdays an hourly service between Sheffield and Gainsborough Central is provided by Northern. This was introduced in the May 2019 timetable change and is the first regular weekday service to Gainsborough Central since 1993. Passenger services along the entire route only run on Saturdays, when Northern operates three services each way between Sheffield and Cleethorpes. At Barnetby, the route is joined by the South Humberside Main Line and the section between there and Cleethorpes is also served by hourly trains from , operated by TransPennine  Express. The Brigg Branch line is single from Barnetby to Brigg, and Kirton Tunnel to Thonock (North of Gainsborough Central) with a passing loop at Northorpe. Other sections are double track. Former routes. Clarborough Junction-Sykes Junction branch. Clarborough Junction is about east of Retford. This Sheffield and Lincolnshire Junction Railway branch had originally been proposed in 1844. It opened on 7 August 1850 The line diverged from the MS&LR main line at Clarborough junction ran through Leverton, Cottam and Torksey to Sykes Junction (located about northwest of Saxilby). Services from Sheffield via the branch line to Lincoln, then continuing  to Grimsby and Cleethorpes via Market Rasen, used to operate along the line. Opening of the line was delayed for four months by controversy over the safety of Torksey Viaduct. It is now a Grade II listed structure, though the line closed to passengers on 2 November 1959. In 1967 the line was reopened from Clarborough Junction to Cottam to serve Cottam power stations and is now solely used for freight traffic. On reopening, Clarborough Junction signalbox was closed and control passed to Thrumpton, and the two level crossings were converted to automatic half barriers. The Thrumpton box was rebuilt  in 2014. Types of train. The line is operated by Northern Trains, which mainly utilises Class 150 sets (though Class 153 single railcars can also appear). From Gainsborough Trent Junction (where the line from Doncaster joins) eastwards to Lincoln, class 153 and Class 156 units operated by East Midlands Railway share the route. The Brigg route is also used by freight traffic between Immingham docks and the power stations at West Burton, Cottam (after reversing in Worksop sidings) and West Yorkshire & the East Midlands. Retford dive-under. The Sheffield and Lincolnshire Junction Railway (S&LJR) (later Great Central Railway (GCR), now  the Sheffield–Lincoln line) was the first railway in Retford, arriving on 6 July 1849. This was then joined by the Great Northern Railway (GNR) line from , arriving on 4 September 1849 with the GNR crossing the S&LJR at a flat crossing. This flat crossing caused congestion as trains could not run on both lines at the same time; this was to become a bigger problem when the West Burton and Cottam power stations were built, as they would require 5 million imperial tons (approx. 5 million tonnes) of coal a year, to be sourced from the National Coal Board 's coalfields in the East Midlands and North East. The flat crossing also placed a speed restriction on express trains using the GNR line. In order to alleviate these problems a dive-under was constructed, by which the GCR passed under a new bridge which the LNER passed over. Construction started in 1963 and was completed in 1965. During construction, trains continued to use the flat crossing. Upon completion of the dive-under the flat crossing was finally removed on 13 June 1965, allowing through trains on the LNER to run at normal operating speeds, and allowing trains to run  on both lines simultaneously. The approach slopes into the dive-under's long channel have a gradient of 1 in 100 on the east and 1 in 133 on the west side.