Assassin’s Creed IV: Owned

Every Island has servals activitys: chests, animus fragments and secrets (letters, notes, treasuremaps and maya statues), to see them all on the map just get to top if a viewpoint and sync.

You find your first Island Abaco Island in the beginning of sequenz 3, this Island has only a few (viewpoint, chest, three fagments and two secrets: treasuremap and letter) collect them and the Achievement is yours.