Me and my girlfriend once stopped at a rest area that was right next to this small mountain you could climb. We went up, and came back down.
Eventually, we both got really horny and started fooling around. Realize that this was during daytime, but located out in the middle of nowhere. When we started getting a little frisky I put her on the table which ended up being perfect level to fuck and waiste height.
She came, and then it was my turn. Riiiiiight when I came, a car pulled in, and I luckily managed to cover my dick up by sitting down.
But yeah, we fucked on a picnic table.