Skyrim Sidelines- Karthspire Camp (Part 3)

The top layer of stone ruins holds the Forsworn forge (and why these people need a forge for their bone-and-leather weapons I'll never understand), which is being worked by one of the Forsworn spellcasters- thankfully not a Briarheart, but still threatening in her own right.  Take her down and you can get access to the food supplies up here, the forge itself, a chest of treasures and, if you're lucky, an expensive weapon sitting on the top of the hay bale.  A more mundane weapon may be atop the workbench, which is also a handy thing to have here right beside the grindstone- if you've just gained a Blacksmithing perk.

Return to the ground level and head East and you can enter the area claimed by the local Hagraven.  Sneaky types will need to be very cautious- hagravens are premier spellcasters and will put shards of ice through your face before you know they know you're there.  Similarly, melee-types will need to be very quick crossing the open ground here if they don't have a shield and the spell-blocking perk for that, as the hagraven can easily back away and kill you with spells as you try to catch up.  Melee sneaks will want to take advantage of the obstruction the hagraven's tent supplies on the right side of the approach.

As for loot in the area, the hagraven's tent is the premier point, holding not only some ingredients outright sitting on an alchemy table, but also a large unlocked chest full of treasure.  There is also a ritual stone nearby, on which lies a dead giant- you can check it for ingredients, and also retrieve the Giant's Toe and Void Salts sitting in the nearby brazier that the hagraven was presumably doing something with.

To round out your experiences here, you'll need to enter Karthspire itself, which is off the third, unexplored bridge from the initial platform.  This bridge leads to a level-ish area with a campfire, where one last Forsworn archer is waiting.  There are stone stairs from the area that will bring you to the cave entrance that grants access to Karthspire.  Karthspire, itself, is the entrance to the Sky Haven Temple, and is thus covered in the main questline articles.