FATMAP difficulty grade
Thieves Forest is an uber-gnarly fall line-filled old school DH descent.
In an attempt to mitigate the straight-down-the-mountain fall line, tight switchback turns have been built, which only serve to make the trail tighter and more difficult.
Expect to surf through loose scree, drop down chunky rock gardens, and encounter root and log drops in the middle of some of the very tight switchbacks.
In reference to this trail, Deer Valley simply says "pads and downhill bike recommended." I'd call that the understatement of the year. Sources: http://cdn.deervalley.com/web/Areas/WhatToDo/Content/pdfs/BikeTrailDescriptions.pdf http://cdn.deervalley.com/web/Content/pdf/planning/trail_maps/DVRSummerTrailMap.pdf