5 is the most, with my ex wife on our first weekend away, I was 18/19 at the time..I felt sorry for the hotel cleaners, quickly had breakfast and checked out!
6 with a wonderful Galway woman when I was much younger. We saw the sun coming up as we finally rested.
Probably about 10 orgasms between us in total. Pints of JD n Coke fuelled night