The legend of the Fenn Treasure is one of the most intriguing modern mysteries.

In 1998, New Mexico art dealer Forrest Fenn claims to have filled an old bronze chest with gold, rare coins and gems and buried the treasure somewhere in the Rocky Mountains.

After hiding the chest, which Fenn values at over $2 million, he published the book "Thrill of the Chase"offering nine clues for would-be treasure searchers.

Several subsequent books have been written by prospectors providing theories. However, nobody has discovered the cache and, to date, four treasure hunters have gone missing while searching for the chest.

While most experts believe the priceless bounty is somewhere in New Mexico or Colorado, two Vox.com reporters suspect that the Fenn Treasure may have been buried near Yellowstone National Park in western Wyoming.

Estelle Caswell and Zachary Crocket, recently documented their journey in "The Hunt For Forrest Fenn's $2 Million Hidden Treasure".