[spoiler]Past library; in cave, stuck

[lake_utuqaq]

I had the same problem and it was very misleading that you can build a giant seesaw using the wooden board and the concrete sewer pipe.

It basically creates itself if you drag the wooden board near the sewer pipe so I assumed I'm doing what the developers wanted me to do.

I wasted a couple of hours trying to figure out how to jump up to the top of the cave using my giant seesaw, until I gave up and started to look for a solution on the net.

http://img205.imageshack.us/img205/4060/seesawud6.jpg