During the summer I was out walking in the woods and as it was a hot day I had a short skirt on and a skimpy t shirt to keep cool. I hadn't pood in six days and I really had to go. I looked for a suitable place to relieve myself but there were a lot of people out enjoying the hot weather and I couldn't find anywhere private. I searched and searched while the pressure in my bowels grew steadily and after an hour I was nearly pooing in my knickers. I had to find somewhere private and fast but there were so many people in the woods I just couldn't find anywhere and I was super desperate. I felt my poo pushing on my anus and it was hard to keep it closed against the pressure that continued to build up inside me. I had to go right now but I had nowhere to hide and I knew I was going to poo myself. I felt my anus open against my will and clenched using all my strength but it hurt and I wanted to relax but I knew I'd lose it if I did. I couldn't let anyone see me pooing myself, so in spite of the pain I was in I kept clenching. Finaly I spotted a particularly dense part of the woods but it wasn't easy to get to as it was off the path and I got scratched as I scrambled into the undergrowth. Once I was sure no-one could see me I lifted my skirt and took my knickers off and squatted. As soon as I got into position I pushed out a six inch turd while peeing a powerful stream and when it broke off it was instantly follows by a foot long turd and then another one of ten inches. I still didn't feel I was done so I kept pushing for a minute and then another turd of only three inches came out. I felt my guts rumbling and then a load of semi solid not quite diarrhoea shot out fast. The relief was so intense it made me horny so I started to masturbate to a wonderfull orgasm. Once I'll was over I when with some dock leaves and put my knickers back on and left my huge pile behind.