Great picture, TT!
I remember that castle well! On the 40th anniversary I was flying HM's mighty Phantom (not very well) and, for once, happened to be in the right place at the right time!
So we flew past the castle, down to 250 ft, across the dam, then climbed out. Seemed like fun, so did it again. Then another jet joined us, so we did a pairs flypast... I recall that there were people waving (I think
) from the castle. Then home for tea at Gutersloh.
Mentioned it to the SNAVO when we were chatting later and he went white. He dug out something called 'Manuel de vol a basse altitude' (not something we air defenders had bothered with before) and pointed out that we weren't supposed to use the dams as a turning point or overfly them at low level.
"Good job we didn't tell him about saying hello to the Moehne Dam on the way home, then!" I remarked to my nav after he'd gone.
But no-one ever complained!