My ex lived on the Jersey Shore, specifically in the Avon-Belmar area. I had just graduated from college and was working in NYC - and decided to have my vacation in her area. I rented a room at a place in the area that did apartments and single rooms for the summer.
One night, we had dinner with her parents - and then walked to the boardwalk and the beach. Since she couldn't stay with me (she was my gf and it was their area), I think both of us we were a bit horny. So we walked on the beach, and I was grabbing her ass a bit. We were chatting and playing a bit, and finally I kissed her hard. We walked some more and then I suggested we go under the boardwalk. Now, I had never done that, and my guess was she hadn't either.
There was about a two foot clearance between the sand and the boardwalk. But when you got to the sidewalk wall - it was about three feet deep from the street above. We started making out, and I started to make a few moves. I went to her tits, playing with them, and opening up her blouse and her bra. I pulled out her nipples and began to kiss them, lick them, and pull them to see how far she would go. She didn't resist, and kept moving my hands on her nipples. I moved then to her pussy, rubbing her, and started to remove her shorts and panties.
I then got more aggressive. I started to push her shorts off, and got them about half off when she said she heard something. Sure enough she was right - a couple walked past above our head. It was then I realized there were people above us - and that really turned me on!! So - I put my fingers in her pussy and pushed for all I was worth. I then fully removed her shorts and panties, so all she had on were the shirt and bra hanging off her shoulders.
I pushed her down and started to move my fingers in and out of her. She was laying on the sand, moving all around, and then mentioned she was getting sand in her hair and up her ass. I took the shorts and put them under her ass, and then took her shirt off and put that under her head. I then looked at her - she was completely naked!