During most of the First World War, Arras was about 10 kilometers (6.2 miles) away from the front line, and a series of battles took place around the city and nearby, including the Battle of Arras (1914), the Battle of Arras (1917) and the Second Battle of the Somme component of 1918's Hundred Days Offensive.
On 31 August 1914, German light cavalry (Uhlans) arrived in Tilloy-lès-Mofflaines, and an army patrol made a foray into Arras. On 6 September 1914, 3,000 soldiers led by General Hans-Jürgen von Arnim barracked within the city and in the citadel. Shortly after, Louis Ernest de Maud'huy's soldiers partly repelled the German army troops, and trenches were dug in the Faubourgs d'Arras. On 7 October 1914 the city hall burned. On 21 October 1914 the belfry was destroyed, and so was Arras Cathedral on 6 July 1915.
In 1917, a series of medieval tunnels beneath the city, linked and greatly expanded by the New Zealand Tunnelling Company, became a decisive factor in the British forces holding the city - particularly during that year's Battle of Arras.
By the end of World War I (1918), the city was so heavily damaged that three-quarters had to be rebuilt. The reconstruction was extremely costly, yet it proved to be a success and allowed the city to expand.
The town is located approximately 11 km (6.8 mi) south of the Canadian National Vimy Memorial built in 1936 on Hill 145, the highest point of the Vimy Ridge escarpment. It is dedicated to the Battle of Vimy Ridge assault (part of the 1917 Battle of Arras) and the missing First World War Canadian soldiers with no known grave; it is also the site of two WWI Canadian cemeteries.
On 9 April 2017, the 100th anniversary of the Battle of Vimy Ridge, Arras Mayor Frédéric Leturque thanked Canadians, as well as Australians and British, New Zealanders and South Africans, for their role in the First World War battles in the area.