What unit sent detachments to the main theatre of war during the First World War?
1st Durham Engineers: The 1st Durham Engineers, later Durham Fortress Engineers, was a Volunteer unit of the British Army's Royal Engineers. 1st Durham Engineers:  Although its main role was defence of the North East Coast of England, the unit sent detachments on active service to the Suakin Expedition, the Second Boer War, and the Western Front and Italy during the First World War. Western Front (World War I): The Western Front was the main theatre of war during the First World War.
The 1st Durham Engineers