Every submitted image has an Ordnance Survey grid reference, which pins it down to a single 1km square in Britain (two letters) or Ireland (one letter). That generates a local map above the photo with a blue ring where the main feature is.
The viewer location can be any distance away but if not a cross grid will always be within the same square. Cross grids include views, longer telephoto shots and normal photos taken near a square border.
When adding your own decide where the primary location is in the view and then use the second black circle to show where you were when you took it.