The entrance to the shrine is actually behind the waterfall above the main path. You'll have to climb up to get there and brave the dangers of the flying dragons who inhabit the area.
Once inside, the shrine you'll find yourself in a very narrow mountain pass. The shrine is contained within behind a sea of angry creatures. When you enter the shrine, there's an antechamber full of dragons and then beyond that is a huge courtyard with a massive imprisoned dragon.
I won't ruin the rest... but bring health packs.