From the start point of this trail to the river, this trail is most heavily traveled and is in good shape. The beginning of the trail is basically cut into the side of the canyon and there are some pretty serious drop-offs in a number of stretches, so be very careful. The trail has some minor rocks, but it is the constant exposure that makes this trail challenging.
Once you hit the Snake River (about 4.3 miles in) the character of this trail changes completely and most people turn around and head back to their car. The next section has a fair about of climbing up some rather steep terrain. In areas the trail is basically non-existent and excellent route finding skills will be paramount in the section from Snake River to the endpoint. Be sure to have the route downloaded to the Trail Run Project mobile app and also be prepared for some route deviation since the cattle in the area will tend to move the trail around a little. You are best to link the two ends with a mix of old roads and doubletrack, but be prepared for some steep going.
It is a great experience and a fun adventure! This is best done in the late spring or the fall to avoid the snakes!