In a sleeping bag while two of my friends slept on either side of me. We were on a week long hike so I had to get some relief. Another time I jerked off under the covers in bed while a friend of mine was laying next to me reading a comic magazine facing the other way. I came pretty fast when I was younger. One more memorable place was at a spa that had a big pool with various whirlpools and bubbly massage things. I was sitting in one corner of the pool among the bubbles with water up to my neck and jerked off. I think I was chatting with my dad while I did it.