Castle Rock Loop is a 2 mile loop trail located near Boise, Idaho. The trail is good for all skill levels and primarily used for hiking and mountain biking.
So the location marker for this is totally wrong. Instead, go to 2421 E Old Penitentiary, Boise, ID 83712.
The hike itself is very very short, amd not very challenging. Takes 15 min to get to Castle Rock from the parking lot, if you are going slow. There are others trails in the area though, so its worth out if you decide to do some additional walking.
Easy hike, sneakers and shorts sufficient with water if going during the day. lots of turns to let you adjust distance. connects with table rock but currently avoiding due to recent fires.