Sergeant Stanley was in Arras in 1917, serving with the Army Ordnance Corps. He took a number of photographs of the town. These are on page 61 of the printed version of his diary.
As well as his own service there, pages 7 and 69 of the printed version of the diary will help you understand why Arras had a particular place in his memory and does for his family today.
Later we know he was at Vimy Ridge, a few miles to the north. The photographs with the map show how the Canadian memorial there has kept a number of trenches to show something of what the area was like during the First World War. There are a number of features at the memorial which match up with Sergeant Stanley's description of living and fighting in the trenches.
Clicking on a marker will give you further information and a picture of the place as it is today.
Many of the places are close together, and you may find it helpful to use the zoom tool to move in closer.
The markers show some scenes in Arras today and the Canadian memorial at Vimy Ridge. You will need to zoom in close to see all the markers.