Olive all'Ascolana are from Ascoli

As one might guess from the name, Olive all'Ascolana are from Ascoli, in the Marches. They are among the best-known Italian stuffed olives, and booths selling them at fairs are invariably mobbed. 

If at all possible you should use olives of the Ascolana strain, which are large, green and mild, and were already renowned in Roman times, though the recipe for transforming them into stuffed olives is more recent, dating to the 17th century. Though they're generally classified as an antipasto, they're a superb finger food and will also work well as a first course, or as part of a platter of mixed fried foods.