After spawning at the Iron Temple in Felwinter Peak, head up the stairs on the left.
About halfway up the steps, you'll see some climbable rocks. So start climbing.
Make your way up to the left first, to the ledges above the wolf statue. Then turn around and jump to the larger platform just below. You'll have gone this way to find a SIVA cluster.
From the platform, scramble up to the pass above. A marker for the medallion will appear when you're getting close.
You'll find it on the ground here.