The secret is quickly getting out on Yading,    
one of China's newest and most topographically extreme natural reserves.  Located in southwestern Sichuan, three snow-capped peaks dominate the reserve's primal forests, shimmering lakes and virtually untouched scenery.  The peaks, named for three Bodhisattvas which they embody, mark some of Tibetan Buddhism's holiest mountains.  The mountains are historically a legendary pilgrimage site where Tibetan pilgrims come from far and wide to complete a Khora (A Tibetan ritual where a pilgrim circumambulates a holy peak).  Fortunately tourist development only affects part of the park, which leaves excellent private hiking options.  The park is at least one full day's drive from the nearest airport which further ensures its seclusion.