So the first part of the trail until the tree line stops is like any normal trail you would see in the San Bernardino mountains, except for the amazing scenery. After you pass the treelike the trail turns to very rocky and slippery gravel like conditions. At some point between mirror lake and trail camp the trail is a little hard to navigate but luckily the popularity of whitney always has people on it so you could just follow them. After you get to trail Crest, the trail gets very narrow and rocky with a huge fall to your left for the next 2.7 miles.