This happened a few years ago, and it's about time I shared it. I'm in my mid thirties bisexual and now married but at the time of this story I was in a shakey partnership with a female bisexual. I'm 5ft 11ins muscular, fair haired with a 6inch cock. I have always had an interest in naturism and always take any oppertunity to get naked. I had a fantastic experience on a beach in North Wales ( just North of Barmouth ) which to this day sticks in my mind as a number one sexual memory. My girl friend and I were travelling down from Snowdonia heading for Bristol it was a hot summers day and we decided to break our journey with some time on the beach. With no knowledge of that coastline we just headed to the beach at the nearest road, found a carpark and headed onto the beach. It was a wide and sandy beach which was not at all busy so we easily found a spot to relax and enjoy the sun. I was lying there watching people, most of whom were part of family groups having fun, then a well tanned man strutted past with a pair of binoculars, he was intently looking down the beach, I looked towards where he was observing and could make out a group of people about half a mile away. He walked off down the beach at a fair old rate which really caught my interest. My girlfriend was dozing so I told her I was off for a wander. The tanned man was well off in the distance by now, I followed with a feeling of what I would discover. Once I got closer to the distant people I could see they were all naked, I knew I really wanted to be naked and be in that area of the beach. I turned around and sprinted back to my girlfriend with my cock rising within my trunks at the thought of being naked in public. My girlfriend was surprisingly happy to move down the beach to the nudist section. We walked past all the groups of naked people and plonked all our stuff down just past the last couple of naked sun bathers. We both stripped off our swim wear, and I immediately lay down on my front to hide my erection that uncontrollably happened with the sensation of sea air on my cock. After a short while I'd calmed down a bit so we walked down to the sea for a paddle. Once in the cool water I looked back up the beach to see the tanned man sitting in the dunes watching us through his binoculars, this really turned me on and my cock responded straight away, I didn't say anything to my girlfriend but gave her a hug and rubbed my hard penis against her leg, she responded and started to gentlty wank me, her back was to the beach so I was able to see the tanned man observing us. The water was just above our knees so I knew that he was able to see exactly what was happening. After a fairly short time my balls tightened and I shot copious gloops of cum up my girlfriends arm and tummy. We then wandered back to our bags and towels which were just below where the tanned man was sitting up on the top of the dunes. My girlfriend was very turned on so I suggested we wander into the dunes so I could give her a bit of oral. We found a cosy dip surrounded by marram grass and settled down. She lay on her back and spread her legs, I got down and started gently licking her clit which rose to my caresses. I was very involved with pleasuring her but when I took a quick breath I realised there was a man of about 65 watching us and playing with his semi hard cock. When he saw me look at him he very politely walked on but stopped a short distance away and continued wanking. This was so exciting I could barely control myself, I wasn't sure weather he was interested in me or my girlfriend but to be performing to an audience was a real turn on. I turned round to my girlfriend who was lying there with her eyes closed and saw the tanned man from earlier sat in the grass just a few feet away, nursing his large swollen penis. I caught his eye and smiled to confirm that it was o.k. him being there. I then eased my cock into my girlfriend and started to fuck her. We had two guys one in front and one behind us, both wanking like crazy and yet my girlfriend was unaware that we were being watched. I became aware that maybe the missionary position was a bit dull so I eased my girlfriend over and slipped my prick in from behind it was at this point that she became aware of the tanned man in front of us but she had no time to comment as he then stiffened and shot his load. The first glop actually landed on my girlfriends back, the rest falling on the hot sand in front of us. I couldn't resist, and licked up the cum on her back, this tasted so good and within seconds I shot my load deep in to her arching body. As I withdrew I glanced behind to receive a grateful wave from the older chap behind us who'd obviously also just cum too. I always love fucking outside as does my wife (not the same person in the story) but this experience always sticks in my memory.