In the 7th grade my family lived in Pennsylvania for a while. Our neighborhood was a cul de sac surrounded by miles of thick woods. You had to take a long road to get to it.
I was hanging out with sketchy friends (boys) at the time. We were going through a pyromania "phase" where we'd go buy things at 7-11 just to take packs of matches when the clerk wasn't looking.
On a mid-fall sunny, dry, wind-less day we wandered into the woods, where all the leaves had turned. Along the way we lit things on fire and put them out, for fun.
About a half-mile in we found a giant branch or tree that had fallen but still had its dead leaves on it. On its side, it was way higher than us and long as a bus. So… of course we began to light it on fire. Idiots.
Before we knew what was happening the entire thing was engulfed in flames that were reaching two stories into the air and licking other standing trees' leaves on fire, which began to sway in the intense heat. This was thick woods. We began screaming and taking off our jackets and stomping with our (sneakered) feet screaming, "Oh my god put it out! Put it out!" I remember choking and feeling the intense heat on my face as I did everything I could to smother a fire the size of a small house. There were only three of us.
At one point one friend said "Just run!" We didn't. Of course if we had run and left it burning, we would have clearly begun a forest fire. Who knows how huge. Luckily we stayed and somehow put it all out.
All our faces and hands were red, and our hair was singed. My friend Dave had actually climbed up into two separate trees to put out a patches of leaves that had caught and were smoking, with his down jacket, which was ruined. All of our clothes were ruined, and my sneakers were literally melted some on the soles.
We wanted to stick around to make sure it was totally out but there was no time. Getting caught was the worst scenario to us. We were sure someone had seen the smoke from afar and called it in. We ran through the woods so fast. My chest and lungs have never hurt so much from running in fear (I already had smoke inhalation). We kept screaming "Don't say anything to anyone!" Over and over as we ran to our respective houses. We didn't! (at the time).
By sheer luck my whole family was out. I grabbed trash bags from the garage and wrapped all my burned clothes and melted sneakers in them and buried them deep in my closet. Then I took a Silkwood shower. I trimmed my bangs a bit to hide the burned part and hoped my parents wouldn't notice my (probably) 1st degree burns on my face and hands.
Somehow, they didn't notice anything, or the missing clothes. (I told my mother days later I lost my sneakers in the creek). My friends also lucked out, and somehow no one blabbed or got caught and no one ever heard about it. We never returned to the spot because we thought someone might be keeping an eye on it. I still think today how we could have started a humongous forest fire.