The Petrified Forest

The Petrified Forest in Calistoga, California showcases an exceptional example of a preserved ancient forest resulting from a volcanic explosion 3.4 million years ago. Located near Napa Valley, this unique site was formed when an extinct volcano, Mt. St. Helena, violently knocked down a prehistoric Redwood forest. Volcanic ash quickly covered the trees, creating an oxygen-deprived environment that inhibited decomposition. Over millennia, mineral-rich water seeped through the ash, saturating the Redwood tissues with silica and forming a three-dimensional fossil through permineralization. This process perfectly preserved even the smallest details of the wood.