It begins at Interstate 5 near Wheeler Ridge , and continues north through the major cities of Bakersfield , Fresno , Chowchilla , Modesto , Stockon , Sacramento , Chico , and Red Bluff . From its southern end at Interstate 5 near Wheeler Ridge to its northern end at State Route 36 near Red Bluff , SR 99 goes through the densely-populated eastern parts of the valley and is a less-direct route than the faster Interstate 5 through the less populated western side of the valley . Cities served include Bakersfield , Visalia , Fresno , Madera , Merced , Modesto , Stockton , Sacramento , Yuba City , and Chico .