There are 4 different types of relics that can be found in Far Cry 3, and although each of the different types give the same experience, the type that they are defines where they can be located. The four different types of relics are Heron Relics; which are usually found high on cliffs and hills, The Boar Relics; which will usually require you to break open a stone wall or door, or a type of barrier blocking a hole or ladder—which can be done with a shotgun, grenade, RPG, etc. The Shark Relics are almost always found underwater, and finally the Spider Relics can most often found behind rocks and other objects.
The acquisition of relics serves no purpose other than XP points—and the “Archeology 101” achievement/trophy for finding half of them, and unlike the rest of the collectibles, there is no story to go along with each, but collectors do so love to collect things! When you approach the resting spot of a relic, you will begin to hear a faint chanting which will increase in volume as you get closer. Once you have plucked a few of the relics from their resting places, the rest will get easier as many of the same techniques used to conceal them are used many times.