Here is the full list of all 12 Hike Isle achievements.
Discovered the Mansion
Discovered the Boatyard
Discovered the Broken Property
Discovered the Magic Mushroom
Discovered the Campsite
Discovered the Tower
Discovered the Hunters Tent
Discovered the Hunters Shack
Discovered the Lonely Tent
Discovered the Timberyard
Finished the game!
Start the game!