sentences:  The interstate then climbs the crests of Jellico Mountain for about another before levelling out on top of Jellico Mountain at an elevation of about and has an interchange with US 25W in the city of Jellico.Less than a mile later, I-75 enters the hilly terrains of eastern Kentucky.Construction of I-75 in Tennessee began in 1958 with short segments in Chattanooga and Knoxville.