Chestnuts are a good source of vitamin C.  They are also high in starch, and can be mashed and used as a potato substitute.  In some communities, chestnuts are distributed to the poor at the Feast of Saint Martin as a symbol of sustenance.  Today, most chestnuts are grown in Japan, China, Spain, and Italy.  Chestnuts are a great ingredient for either a simple snack or a special sidedish.  For a special meal, try adding chestnuts to you favorite stuffing recipe, or braise pork with chestnuts.