Far Cry Primal recycles the map of Far Cry 4.
The world map of the recently released Far Cry Primal bears a lot of similarities to the one found in 2014's Far Cry 4.
Gamepressure captured two screenshots of of the heightmaps in both games to illustrate this, even highlighting the rock formations and bodies of water surrounding them. The actual levels on the ground may very well be completely different in Primal, even if it doesn't look that way from a top-down perspective.
Ubisoft used the same trick in the Blood Dragon off-shoot, though that standalone release cost less, had less features and was a lot shorter.
Here's the Far Cry Primal map:
And here's the same map in Far Cry 4: