Forest is located at 37°21'47" North, 79°17'24" West (37.363333, -79.290000).
According to the United States Census Bureau, the city has a total area of 14.70 mi2 (38.07 km2). 14.61 mi2 (37.85 km2) of it is land and 0.09 mi2 (0.22 km2) of it is covered by water. The total area is 0.58% water.
Forest is located in the Eastern Standard Time (EST) timezone, GMT-05:00. It observes Daylight Saving Time (DST).