As all reviews say, Mailbox Peak is really no joke. It is a 2.5 mile Death March for the unprepared, and an ass kicking workout for the prepared. Don't let the mere 2.5 miles fool you.
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Welcome to Mailbox Peak.
This part of the trail you are under the tree canopy and more often than not you will run into some serious mud, roots, logs and assorted things you have to climb over or around. The switchbacks are more like s-turns as they seem to not want to give you much of a break and just push you up up up the hill. If anyone says "it gets easier" or "you're almost there"...they are lying :)
After what seems to be an eternity, eventually you will break out of the tree line and will finally have some nice scenery with lots of flowers and big views, but the most apparent view will be the huge boulder field in front of you. If you are not up to the scramble challenge, just follow the left edge of it, the trail will be apparent. Plenty of false summits, but I do think once you are out of the tree canopy, the going gets much easier and even if it is muddy, it seems there is more rock mixed in for better grip. Eventually you will reach the mailbox.