As you get further upstream, you begin to see what is leaking so much lava. You also see a few more little red boats but you ignore them. The thing thats letting off the lava comes fully into your view. Its a huge, grey castle! You run up to it and try to get in but the door is locked. You walk around it a bit and find a small hole leadng inside.
To crawl inside the hole click here
To try to jump onto the nearest boat click here