The Petrified Forest
Millions of years ago, after the formation of the Andes mountains, volcanic ash covered the early forests -- killing the trees, but preserving them from decay. Mineral-saturated water seeped through the ash and into the buried logs, filling the empty cells of the decaying wood until they fossilized and turned to stone.

Considered to be one of the world's best petrified reserves, the Petrified Forest has many trees that measure more than 10 feet in diameter and 90 feet long. Compared to petrified trees in the United States and Australia that measure less than six feet in diameter, the trees of the Central Steppes are significantly larger.