Big Wall
CommunityCommunity-sourced: based on player reports and not yet verified by this site.
Go beyond the wall. Find a way past the wall that surrounds part of the island.
Platform:Steam
The 'Big Wall' achievement is earned by going beyond the wall. There is a large wall somewhere on the island, and reaching the area on the other side triggers the achievement. Community guides treat it as an exploration milestone rather than a puzzle.