The Ordnance Survey of Jerusalem of 1864–65 was the first scientific mapping of Jerusalem, and the first Ordnance Survey to take place outside the United Kingdom.[1] It was undertaken by Charles William Wilson, a 28-year-old officer in the Royal Engineers corps of the British Army, under the authority of Sir Henry James, as Superintendent of the Ordnance Survey, and with the sanction of George Robinson, 1st Marquess of Ripon as Secretary of State for War. The team of six Royal Engineers began their work on 3 October 1864.