The eastern third of Tennessee lies in the Eastern Time Zone; Middle and West Tennessee are in Central Time Zone, one hour earlier. The time zone line runs a slanted course from Signal Mountain in the south to the Big South Fork National River and Recreation Area in the north. The time zone line falls at milemarker 340 along I-40, just west of Rockwood and a few miles east of Crossville. Chattanooga, Dayton, Rockwood, Crossville, Rugby, Fall Creek Falls State Park, the Catoosa Wildlife Management Area, and Big South Fork lie close to or on the time zone line, and visitors to these areas should take special care to ensure they are on the right clock.
© Susanna Henighan Potter from Moon Tennessee, 5th Edition