CHIAVENNA, kyä-vĕn′nȧ (Lat. Clavenna, probably from clavis, key). A town in north Italy, picturesquely situated north of Lake Como, on the Mera, at the mouth of the Bregaglia Valley, through which passes the road to the Engadine. The beautiful Church of San Lorenzo has a campanile rising from an arcaded inclosure, and a baptistery containing a Thirteenth-Century font (Map: Italy, D 1). Interesting, also, are the ruins of an unfinished castle, and the Giants' Kettles (marmitta dei giganti), in the Capiola Valley. The chief trade is in fruit and wine, and the chief manufactures are silk, cotton, beer, and a coarse ware cut out of a soft stone found in the neighborhood. The situation made the ancient Clavenna one of the most important keys to the Alps. Population, in 1881 (commune), 4292; in 1901, 4788.