Dit is wat ik heb gevonden op Gamefaqs:
Unlocking PoP1
Soon after you get your first new sword, you'll head into an ancient basement with a lot of open space. Near the end
of that run, you'll find yourself at a switch that rotates. Rotating it
ninety degrees will open the gate in front of you, but you can rotate it
another ninety degrees. Hit the wall it'll point at three times to knock it
down. That will officially unlock PoP1. At that point, you can continue
through the now-open gate and play right away (you'll be prompted to save
first, because you can't go back), or you could just continue on as normal
and access the game from the main menu.
Misschien is dat ongeveer de plek waar je aan 33% van het spel zit ofzo...