The elevation gain posted here is correct but not the is at least 1 mile longer than the posted 9 miles if you do the loop...definitely recommend getting there early to avoid the heat and the crowds that come later...I usually try to start around 6 am. Hiking poles aren’t needed but could be useful for some people. Depending on the weather conditions when you do this hike, I think 2-3 liters of water should be fine.
From the Cobb Estate gate it is about 2.5 miles up to Echo Mtn. From there you can either start with the San Merrill trail or the Castle Canyon to get to Inspiration Point and use whichever one you didn’t take up to get back down to Echo. My GPS measured Castle Canyon to be about 1 mile shorter.
Distance- 10.1 miles
Duration- 4-6 hrs
Difficulty- hard

*easy to find street parking and no Adventure Pass needed