Answer: SWITCHBACK

AnswerCrossword Clue
SWITCHBACKZigzag on a hike
SWITCHBACKZigzagging road
switchbackA roller coaster
switchbacka zigzag mountain railway on which the train shunted back at each stage / to follow a zigzag course esp for ascent or descent
switchbackA 180░ bend in a road or path, esp. one leading up the side of a mountain
switchbackA road, path, or railroad with alternate sharp ascents and descents