I was going to Mount Hagen to get the valerian root there, but my horse, the one Arthur gets at the beginning of the game, died.
Let's say he didn't stop instantly before falling off a cliff. I didn't have any equine resuscitator with me, so I had no choice but to kill him. Now, I have my saddle in hand, at the top of Mount Hagen, on my way to Lake Isabella to pick up the white Arabian there.
Wish me luck.