The Lost Valley Redoubt is a sprawling ruin at the southwestern portion of The Reach and is located about halfway between Markarth and Falkreath. It is situated at the river-head of the Karth River. The ruins are home to an encampment of Forsworn and Hagraven. At the top of the waterfall, near Bard's Leap Summit (behind hide screens), a Word Wall is guarded by two Hagravens. If one sneaks up on them, it is possible to catch the hags performing the dark ritual which turns a human Forsworn into a Forsworn Briarheart. The Briarheart may revive and attack the player.
If sneaking through the Forsworn encampment to reach the top, the dialogue of the Forsworn centers around the fact that one of them has decided to give his heart to "the hags" and become a Briarheart.
If the Dragonborn jumps off the nearby Bard's Leap Summit and survives, the ghost of a Bard will tell a story and increase the Speech skill by one.
It's possible to use Unrelenting Force on the Hagravens or Briarheart at the top of the cliff, only to have them land in the deep pool of Bard's Leap Summit and survive. The player must then face them again if they travel back down the valley.