CALISTOGA, Calif. — About 3.4 million years ago, a violent volcanic explosion erupted within the Mayacamas mountains. The blast knocked over entire forests and buried the hills behind Calistoga in a thick layer of ash.
Then, for thousands of years, mineral-rich water percolated into the pores of these ash-covered redwood trees, petrifying and preserving their shape until they were finally discovered by an old man and his goat.
Charles Evans was his name but those who knew him well called him Petrified Charley, the founder of Calistoga’s Petrified Forest, home to the world’s largest petrified trees.
Janet Angell is one of the current co-owners of the Petrified Forest. Her great-aunt, Ollie Bockee, bought the property from Petrified Charley back in 1914 and it has been a woman-run business ever since.
“The petrified trees in this forest range from 8-feet in diameter to 65-feet long, and yes they are hard as rock,” Angell said.
When Petrified Charley discovered them in 1870, he saw the trees as an opportunity to make money off of weary travelers.
“Petrified Charley charged them a small amount to view the petrified wood,” Angell said.
He welcomed hundreds of visitors to his homestead and spent years unearthing the petrified trees on his land. One of the most well-preserved trees on the property is known as the Monarch Tree.
“Scientists say this is the best petrified tree in the world,” Angell said.
The reason these are some of the best petrified trees in the world is because of the amount of volcanic ash that covered them. Some geologists believe there was actually several volcanic eruptions over the years.
“I’ve been told scientists have measured it at about 1,600-feet above the property,” Angell said
The sheer weight of the ash and lack of oxygen prevented the trees from rotting away, and over time, turned them to stone. Eventually, years of erosion exposed the trees so Petrified Charley could find them.
Charley shared them with travelers, including novelist Robert Louis Stevenson, who wrote about Charley in one of his books.
“He wrote 'Treasure Island,' 'Kidnapped,' and 'Silverado Squatters' which was a travel guide through the Napa Valley,” Angell said.
In a way, Petrified Charley created Napa Valley’s first tourist trap, offering visitors an up-close look at a geological wonder that only happens under rare conditions.
“The type of tree, the fact that they were in a grove, and they were the perfect distance from Mt. Saint Helena, not too close to get burned and not too far away to get the petrification,” says said.
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