Umm, if you jump over the wall at the far end of the field and keep going straight from there, you'll hit it. There are ladders that go down into it, but they're not very sturdy, so you'd probably want a rope or something to get down. And there were broken down cars and things around the edge of it.

The dragonflies usually attack in big swarms, I guess. They have really sharp teeth and they're kinda hard to hit cause they can fly.

I'm Sora! I'm guessing you don't know me?