Need Help with a Plot Hook

I am running a homebrew world that is based around the Neolithic era. Caveman, stone tools, and I'm making a system where magic is a strong raw source. I am including these 8 "wells" of magically divine power (basically really intricate dungeons or events for the party to interact with). And I am struggling to find ways to get them to want to go outside of magic is cool. Any ideas would be greatly appreciated. If it helps the first location is a massive dungeon built inside a bio-illuminescent mushroom, that is filled with decaying creatures and undead. Once again any advice or thoughts would be treasured!