The driver of a vehicle traveling through a defile or canyon or on a mountain highway shall hold such vehicle under control and as near the right-hand edge of the highway as reasonably possible and, except when driving entirely to the right of the center of the roadway, shall give audible warning with the horn of such vehicle upon approaching any curve where the view is obstructed within a distance of 200 feet along the highway.
OCGA § 40-6-245