Filled with 2-3 million dollars worth in gold and jewels, Forrest Fenn's treasure is 'somewhere north of Santa Fe in the Rocky Mountains'. In Forrest's memoir 'The Thrill of the Chase', he published a poem that gives you the clues as to where to find the treasure.
For more on the treasure, check out these sites:
Forrest Fenn - http://www.oldsantafetradingco.com
Thrill of the Chase - http://dalneitzel.com
Chase chat - http://www.chasechat.com
The Huffington Post on the story