When I took this photo during the summer of 2008, I was standing in the middle of Windsor Bridge, the pedestrian- and cycling-only road bridge that spans the River Thames, separating the towns of Windsor and Eton.
It was taken during the last few days of my trip, on a warm, rainy day. The clouds were chasing me from visit at Windsor Castle (way to the left of this photo and out of the shot) all the way to Eton College (about a kilometre away from this point to your right) and managed to catch up with me just a few minutes after I took this photo. I was soggy when I arrived at the College.
Windsor Bridge has long been a connection between the two towns with the original one dating back to the 12th. This current bridge was built in the 1820s as a toll bridge at first.
When visiting Windsor Castle, my recommendation is to spend a few more hours visiting Eton College. Unless you can’t walk any longer distance, you will eventually cross Windsor Bridge and see this view.
Of course, the most important thing to do is to visit the castle itself. It’s the official residence of the Queen and its full of history, art and amazing architecture. Check out the official video released by the British Monarchy: