The Rock is not the huge looming sentry portrayed in films and in Prudential ads. If you have this image of The Rock "guarding" the entrance to the Mediterranean from the Atlantic, then you really ought to see the place, as we did last summer.
Gibraltar is a small, very rugged lump of prehistoric limestone which isn't even an island (although it HAS been) described as follows at www.gibraltar.gi:
"For now it remains as a narrow peninsula stuck to the end of the Iberian Peninsula, linked to it by a narrow isthmus. This isthmus, covered by buildings and a runway, is sandy. You can still see this sand on the surface in places, often littered in marine shells from a more recent past when the sea separated Gibraltar from the rest. This would have last happened during the latest warm period of the glaciations, probably around 120 thousand years ago. Many still refer to Gibraltar as an island. Historically, biologically, even politically it has been an island even in recent times, but physically it is a peninsula."
As for Gibraltar "guarding the Straits Of Gibraltar" connected the Med to the Atlantic, well, it just ain't so. The "rock" is well set off to one side of Algeciras, the Spanish port where you may embark on a ferry to Morocco. The strait itself is fairly wide, and unless the weather is really clear, it IS possible to sail the straits and never see the Rock at all - it's that far over on the Spanish side of things.
In fact, when Gibraltar first comes into view, your first and general reaction is, "That's IT?!?! That's what all the fuss is about?" In other words, it ain't that big, and if it's the least bit foggy, you can easily miss it until you're right on top of it. And, as that webpage says, adjacent to the Brits' property on that peninsulary isthmus are sandy beaches that are, ahem, part of Spain. The border there is not at all apparent from the sea.
I'll cut the Royal Marines a little slack on this one. Too easy a mistake to make. Sorry, Virginia, but the Rock Of Gibraltar doesn't look like the Prudential. It's pretty puny.
Michael
The Brits may well have inadvertantly avoided being decimated by troops of ferocious baboons who inhabit it. Remember them??