The location itself was not that exciting, namely a beach in France, but the circumstances were very interesting.
My wife and I were having a child free week’s camping in early June one year, and were taking the opportunity to be as rude as possible.
A day sunbathing on the beach, lots of suntan lotion being applied to my wife’s legs and buttocks gave me a decent hard on, which she very kindly sorted out for me.
I convinced my wife to allow me to finger her to orgasm; she came quickly and loudly; it would’ve been better if we’d been watched, but there were very few people about.