This tree, located on Mount Etna in Sicily, is the largest and oldest known chestnut tree in the world. Believed to be between 2,000 and 4,000 years old, this tree's age is particularly impressive because Mount Etna is one of the most active volcanoes in the world. The tree sits only 5 miles from Etna's crater. The tree's name originated from a legend in which a company of 100 knights were caught in a severe thunderstorm. According to the legend, all of them were able to take shelter under the massive tree. It is listed by Guinness World Records as having the "greatest tree girth ever," at 190 feet in circumference.