Alleghenies
a word used as synonymous with the APPALACHIAN MOUNTAINS (q. v.), sometimes applied only to that portion of the system which extends from Pennsylvania to North Carolina, and which forms the watershed between the Atlantic and the Mississippi. The ridges, 2,000 to 2,400 feet high, are remarkable for their parallelism and regularity, all the main valleys being longitudinal. They are rich in coal, iron, and limestone, and their forests supply valuable timber.