[2] The current route of the Durham Coast Line has its origins in some of the earliest locomotive-operated railways in North East England.

As with many of the early railways, this line was constructed primarily for the transportation of coal from western and central areas of the Durham Coalfield to the River Tees at North Shore (in Stockton), and Port Clarence.

Despite major financial difficulties, this line was opened to mineral traffic in 1833, but did not carry passengers until July 1835, when a service was introduced between Coxhoe and Stockton (Clarence).

The HD&R was first authorised by an Act of Parliament obtained on 1 June 1832 to construct a 14-mile railway from Moorsley (near Houghton-le-Spring) to Hartlepool with several short branches to serve collieries surrounding the line.

[3] Combined with the 1873 realignment of the south to east curve at Norton Junction, which eased the severity of its curvature,[3] this massively improved the connections between Hartlepool and the rest of the Teesside region.

The rope-worked 1 in 34 incline at Hesleden Bank was realigned in 1874 to reduce the gradient to that of 1 in 52 and thus enable locomotive working over the entire Hartlepool-Sunderland route.

[7] Following the opening of Sunderland Central station, NER and LS&SR services were diverted away from the earlier termini and focussed in one location for the first time.

[17] The line opened on 1 April 1905, with new stations constructed at Blackhall Rocks, Horden and Easington,[18] to serve the new villages that had been created to house workers from the new coastal collieries which came into existence thanks to the provision of the railway.

[19] The other notable improvement during this period was the opening of additional stations at Blackhall Colliery on the NER-built Seaham to Hart line in 1936,[17] and at Seaburn on the former Brandling Junction Railway in 1937.

[3] These closures included the inland West Hartlepool to Sunderland route through Haswell (the main line between the two towns until 1905), which lost its passenger service on 9 June 1952.

[20] Despite this apparent degradation of passenger services, British Rail did implement some improvements during this period, including the replacement of the original station at Billingham with a newer one, closer to the modern town centre on 7 November 1966.

[26] The former British Rail stations on the Durham Coast Line at Felling and Pelaw were closed on 5 November 1979, in order to enable their conversion for use by the Tyne and Wear Metro.

[27] The Metro line between Haymarket and Heworth opened in November 1981, and as a result, the British Rail station at Gateshead was closed just one week later.

[29] Metro services were extended to South Hylton from 31 March 2002[30] before the extension was officially opened by Queen Elizabeth II on 7 May, as part of her Golden Jubilee celebrations.

The ultimate goal of a half-hourly service and new stations (Phase 2) was put on hold when the Strategic Rail Authority came into being and funding disappeared.

[21] This included £4.4 million from the second round of the Department for Transport's New Stations Fund and additional contributions from Durham County Council and the North East Combined Authority.

These fleets were both introduced in the late 1980s but are currently being fitted with free Wi-Fi, power sockets, on-board passenger information displays, and an interior refresh as part of Northern's ongoing refurbishment programme.

[41] Other rolling stock includes Grand Central's Class 180 diesel multiple units, which provide five daily services between Sunderland and London King's Cross,[42] and LNER's Class 800 Azuma used on the once-daily service to and from Sunderland and London King's Cross, previously introduced by Virgin Trains East Coast in December 2015.

Cement is delivered to Seaham Docks, and scrap metal is forwarded from Stockton on Tees to Celsa EAF works in Cardiff.