This friday (the 13th), I rode my bike, after work, to the local forest preserve to use thier public shelter for the night. My wife and son are in the States visiting my family so I wanted to get out and "play". There were some people who came by along the paths, and two girls were occupying the shelter across the field from me. At about 10:30 pm two guys (20's) and thier girls friends came by and wanted to use the shelter and when they heard that I was going to be there all night they got a bit upset but went off. I kept my eye on them since I didn't like their tone, and didn't they come back, but this time quietly and in a round about path to the shelter. But I was in the shadows watching and when I stepped out saying "hi there!" the guys played tough and said thay came "to take some fire wood" (all the shelters have alot of precut wood for the public). That was fine since I already had plenty put to the side incase it rained in the night. Some time went buy and my instincts told me something wasn't right so I packed my pack with the valuables which I couldn't keep on me and hide it in the forest. After about another hour something still wasn't right so I decided to go into the forest just out of the fire light which gave me back some of my night vision and gave me a clear veiw of the two paths which led to the shelter.
Just as I got into the forest two OTHER guys come bursting into my camp to have a look around (the only thing in the shelter was my theromrest and sleeping bag). They didn't do anything and soon left. I waited awhile and then headed around to were my pack was hidden, retreived it and got to the shelter and packed, that was at about 1:30 am.
I made sure that I had everything I needed on me (fleece, warm hat, rain pants in my pocket, a packet of biscuits, my cell phone (on "silent"), boots well tied, Leatherman and PSK were I could get to them and my Fallkniven A1 on my belt). I drank as much water as I could from my MSR water bladder, grabbed the cup of coffe I had just made and headed off through the woods.
I had ,as always, reconned the area around my camp so knew were I was going to go which gave me the best spot to watch the fire at my camp and the surrounding area (there was some activety around my camp). There I sat quietly until the sun came up (beautiful!!) and got on my bike and came home.

Today (sunday) I went back and found that one of the shelters (the one which the girls were staying in) was completely burned down along with a small house near by, apparently some people were sniffing lighter gas and started a fire with gasoline.

After thinking about what happened I was happy that I:
1)knew the area around my camp
2)knew how to move through the woods
3)had all the essentials (water, food, warmth and defense near me)
4)had patience and confidence

Sorry that this was so long, but has anyone else had similar experiences?