ATITLÁN, or Santiago de Atitlán, a town in the department of Sololá, Guatemala, on the southern shore of Lake Atitlán. Pop. (1905) about 9000, almost all Indians. Cotton-spinning is the chief industry. Lake Atitlán is 24 m. long and 10 m. broad, with 64 m. circumference. It occupies a crater more than 1000 ft. deep and about 4700 ft. above sea-level. The peaks of the Guatemala Cordillera rise round it, culminating near its southern end in the volcanoes of San Pedro (7000 ft.) and Atitlán (11,719 ft.). Although the lake is fed by many small mountain torrents, it has no visible outlet, but probably communicates by an underground channel with one of the rivers which drain the Cordillera. Mineral springs abound in the neighbourhood. The town of Sololá (q.v.) is near the north shore of the lake.