How does one get to the top of the mountain at the end of the game? Where's the path? Every source I read or look at just assumes you're there. I did finish the bunker, and came back down by the grassy area near where I came in by boat. Thanks!

Maybe you have not activated the mountain puzzle yet.
Check the walkthrough here and see if you can find out what's holding you back from getting to the mountain.

If not - maybe someone who has played the game can help us.

Thanks, MaG. I did go back and adjust the laser in the city. Don't know if it was that, or the fact that I tried getting across the water a different way...perhaps I just missed 'seeing' a path that was there. Either way, I did finally get in! Thanks again...

Great that you got to the top of the mountain now.