All documents, relics, and GPS caches found!

This will be the final collectible-related achievement you will obtain within the game. As mentioned before, there are a total of 54 documents, 42 relics, and 75 GPS caches to be found around the island. While their locations are not directly noted on the map at first, completing the optional Tombs in each area will net you a Treasure Map for that particular area of the island. This will then mark the collectibles on the map and finding them should be quite simple.

Remember, you can always come back to the game after completing the main storyline, so do not feel compelled to snag all collectibles before finishing the story. In fact, many of them will be unobtainable for some time until you progress through the story and obtain new gear or equipment.

As always, utilizing the Fast Travel Camps will help you move around the map quickly, if you choose to hunt down these collectibles post-game. In the Fast Travel Menu, you will also be able to see how many collectibles you are missing per area of the island.