nvubu:
I think you are right. It is the fort at Sharjah. It does look bigger than I remember it and that is not the control tower that I remember. The latter was obviously demolished and the new one built alongside the fort. I have been searching for a decent photograph of the fort in my collection but the only one I can find that fits the bill is this photograph of JW Mecom Lodestar N5231N which I took in 1970.
Sorry for the confusion.
JW411