The Battle of Messines begun on June 7, 1917 and last a week until June 14. The offensive was an assault to capture the German defensives on a ridge running south of Ypres and also to draw German soldiers to Flanders from the Arras and Aisne Fronts and thus relieve pressure on the French soldiers who were struggling at the time.
The battle begun at 3.10am with detonation of 19 mines which was followed by a creeping barrage, artillery fire that slowing creeps forward, for some 640m (700ft) which allowed the Allied troops, supported by tanks and aircraft, to secure the ridge. The secret to the success were the mines, since 1916 the British had been tunnelling the area digging 22 mine shafts, some as deep as 24-37m (80-120ft) below the surface with many of the Allied mines lying below German ones. In total more than 8000m (26,400ft) of tunnels were dug. One mine, at Petit Douve Farm, was discovered by the Germans and destroyed with another 2 not being detonated because they were out of the planned attack area.
The Allied bombarded the German lines for more than 2 weeks before the assault constantly firing more than 2300 guns and 300 heavy mortar ceasing only 2.50am on the 7th June, 20 min before the assault. More than 600 tonnes of explosives were detonated leaving General Plumber, the man who orchestrated the attack to say;
“Gentlemen, we may not make history tomorrow, but we shall certainly change the geography”
It is said that British Prime Minister, Lloyd George, heard the explosion in his study at 10 Downing St. London. The effects were devastating, 10,000 German soldiers died instantly allowing for troops to take their primary objectives in 3 hours. The Germans counter-attacked from the 8th until the 14th June by which time the area was totally in Allied hands.
The 2 mines that remained undetonated on June 7 caused a huge problem for local townspeople as the British lost the maps with their location. One exploded on 17th June 1955 (killing a cow) in a lightning storm but second one is a bit of a mystery with its location still being unknown.
It is estimated that in the week of the battle the Germans had 25000 casualties and the allied 17000, unfortunately one of those was Private Thomas Gardner whose name is now honoured on the Menin Gate in Ypres