During World War I, it was the only coastal defence unit to engage the enemy, and it also trained siege gunners for service on the Western Front.

An invasion scare in 1859 saw the creation of many Volunteer units composed of part-time soldiers eager to supplement the Regular British Army in time of need.

The family brewery introduced Double Maxim brown ale in 1901 to celebrate the detachment's return and the beer is still brewed in Sunderland.

[21] By the autumn of 1914, the campaign on the Western Front was bogging down into Trench warfare and there was an urgent need for batteries of heavy and siege artillery to be sent to France.

[14] On the morning of 16 December 1914, a German naval force under Rear Admiral Franz von Hipper approached the coast of North East England to mount a Raid on Scarborough, Hartlepool and Whitby.

Lighthouse Battery scored a direct hit on Blucher's forebridge, disabling two guns of the secondary armament, but suffered a number of misfires due to an electrical fault.

The commanding officer and three gun captains of the Durham RGA were later decorated, Lt-Col Robson receiving a Distinguished Service Order, Sgt T. Douthwaite a Distinguished Conduct Medal for extracting a live cartridge from the breech of the Lighthouse Battery gun after a misfire, and Acting Bombardier J.J. Hope and Bombardier F.W.

[23][24][25][27][29][30][31][32] In 1920, all members of the Durham RGA in action that day were made eligible for the British War Medal, normally only awarded to those who saw active service overseas.

The battery formed part of 34th Brigade, RGA, and sailed with it to France on 9 December, equipped with four of the latest Vickers BL 6-inch 26 cwt howitzers.

RGA brigades were redesignated Heavy Artillery Groups (HAGs) in April 1916, and the policy now was to move batteries between them as required.

The remaining section fought throughout the 'Great Retreat' and supported the Australians at the First Battle of Villers-Bretonneux where they decisively stopped the German advance on that front.

[40][41][42] 41st Siege Bty was in action when the Allies launched their counter-offensive at the Battle of Amiens on 8 August, and then followed the advance of Fourth Army to the Hindenburg Line.

[14][46][36] In April 1917 142nd Heavy Bty supported the Canadian Corps' successful attack on Vimy Ridge as part of the Arras Offensive.

[54][55][56][57] On 28 June 79th Bde supported XI Corps in a limited counter-attack on La Becque, which was described as 'a model operation' for artillery cooperation.

[47] It was among the mass of artillery supporting IX Corps' assault crossing of the St Quentin Canal on 29 September,[63][64] and continued with it at the Battle of the Selle on 17 October, when one German counter-attack was broken up when all available guns were turned onto it.

[68] As the regimental historian relates, 'The guns of Fourth Army demonstrated, on 23 October, the crushing effect of well co-ordinated massed artillery.

[69] IX Corps stormed across the canal on 4 November (the Battle of the Sambre), after which the campaign became a pursuit of a beaten enemy, in which the slow-moving heavy guns could play little part.

[73][74][75][a] The Nominal Rolls of the battery show large numbers of men with home addresses in Hartlepool and the surrounding area.

[77] Commanded by Major Daniel Sandford, 94th Siege Battery landed in France on 30 May 1916 equipped with four BL 9.2-inch howitzers Mark I and immediately began preparing to support Third Army's Attack on the Gommecourt Salient on the First day on the Somme.

On Z Day 94th Siege Bty succeeded in firing 100 rounds per gun in the 65 minutes preceding the attack, a remarkable feat that caused significant damage to the howitzers' buffers and recuperators due to overheating.

The battery took part in minor operations on the Ancre in early 1917, including CB fire for II Corps' attack on Miraumont on 17 February.

Following up was especially difficult for the heavy artillery, with all the roads forwards having been destroyed, and 94th Siege Bty had to haul its howitzers across the devastated countryside.

It joined Second Army for the Battle of Messines, being involved in exchanges of CB fire with Germans batteries before the explosion of huge mines launched the successful assault on 7 June.

Most of 8 April (which should have been the day of the attack) was devoted to CB fire to neutralise every known enemy gun position and observation post (OP), and to complete the wire-cutting.

VII Corps' two right-hand divisions were held up in front of the Hindenburg Line, where the distant wire had not been cut, but the two on the left penetrated as much as 2 miles (3.2 km) into the German positions, with relatively light casualties, largely thanks to the artillery support.

By April 1918 the Tees and Hartlepool guns were organised as follows:[14][100][101][102] After the Armistice with Germany, the TF was demobilised and the Durham RGA placed in suspended animation in 1919.

[112] From late 1942, with the danger of invasion having passed and with demands on manpower from other theatres, the UK's coast defences began to be reduced.

[112][120][124] The manpower requirements for the forthcoming Allied invasion of Normandy (Operation Overlord) led to further reductions in coast defences in April 1944.

By this stage of the war many of the coast battery positions were manned by Home Guard detachments or were in the hands of care and maintenance parties.

[128][129][134][135] The following served as Honorary Colonels of the unit and its predecessors: A memorial plaque was placed at Heugh Battery to mark the spot 'where the first shell from the leading German battle cruiser fell at 8.10 am on 16 December 1914 and also records the place where during the bombardment the first British soldier was killed on British soil by enemy action during the Great War 1914–1918'.