to the north-west, were nine more strong points. The redoubt was triangular, with an extension to the east across the Thiepval–Grandcourt road and had a frontage of around . At the end of July 1915, fresh troops were observed moving into the French positions north of the Somme, opposite Reserve Infantry Regiment 99 (RIR 99) and on 1 August, were identified at Thiepval Wood as British soldiers ("dressed in brown suits"). Lessons learned during the battles in Artois and at the Battle of Hébuterne near Serre in 1915 and at the Battle of Verdun in 1916, were incorporated into new defensive works as the signs of a British offensive on the Somme front multiplied. Prelude German preparations More fortifications were built, especially in the intermediate, second and third positions, near the and redoubts. New battery positions were built to accommodate artillery reinforcements, dugouts were deepened and extra exits were added. Engineers sited and designed new trenches and stringently inspected the building work performed by the infantry. In early March 1916 and from the chief engineer of the 2nd Army inspected the first position in the area of the 26th Reserve Division; only in the area of Reserve IR 119 at Beaumont Hamel and the trenches to the west around Hawthorn Ridge Redoubt, were there enough shell-proof concrete posts. By July 1916, the German front line from Thiepval to St Pierre Divion was obstructed by sixteen rows of barbed wire and the second line lay behind five rows. Shell-proof dug outs deep, could accommodate all of the trench garrison. British preparations In the British front sector allocated to X Corps (Lieutenant-General Thomas Morland) at Thiepval, the Royal Engineers dug a series of Russian saps into no man's land, ready to be opened at Zero Hour and allow the British infantry to attack the German positions from a comparatively short distance away. Russian saps in front of Thiepval were the work of 179th Tunnelling Company, which also prepared such saps further south at Ovillers and La Boisselle. In the X Corps section allocated to the 36th (Ulster) Division (Major-General Oliver Nugent), ten Russian saps were dug from the British lines into no-man's land, north-east of Thiepval Wood; each of the tunnels housed two mortars. Field artillery support was to come from the 36th (Ulster) divisional artillery, part of the 49th (West Riding) divisional artillery and a regiment of French guns. A large