Miller Trail is mostly level and is frequented by horses more than hikers. There are a number of meadows to pass though and you'll need to cross a road, so watch out for cars. People aren't expecting bikes to come out of the woods around here!
This is a short section of the more typical route to ride on the Timothy Lake Loop
. This trail connects to the Headwaters Trail #522
on the eastern end where it passes across the Pacific Crest Trail.