Always check road conditions before leaving in case of any closures, major delays or weather impact… it may affect your decision on which route to take!
From LA /Orange you have 2 options to get to Kernville, both around 3 hours.
Take 5N to 99N to 178E towards Lake Isabella & then north on the 155 to Kernville. This road takes you through the Kern River Canyon, which is very picturesque with dramatic views of the Kern River. This is the shortest route. Be aware that this is a 2 lane, wind-y road for about 15 miles through the canyon, so if anyone in your group gets car sick, plan ahead to make some stops at some of the pullouts. Also, there are “commuters” on this part of the road that are trying to get through quickly, so be mindful of pulling over when it’s safe to do so at one of the turnouts to let them pass. They’ll appreciate it!
Take 5N to 14N to 178W and then right on Sierra Highway towards Kernville. This route is slightly longer but offers some nice desert scenery & beautiful areas as you transition from the Mojave Desert to the Southern Sierras. You’ll drive through Red Rock Canyon & the Desert Conservation Area in Walker’s Pass. This route is also a great option if the Grapevine at the 5 is closed or hazardous due to snow in winter.
Like from Los Angeles/Orange, you also have 2 options to get to Kernville: Via the 5N to Bakersfield then 178E or the 395 to 178 west through Mojave. It really depends on traffic & road conditions or your comfort level with a canyon highway or simply which kind of scenery you’d like to experience. Both options can result in similar travel times, but the 5 to Bakersfield offers more options of fuel & food stops.
The best option from points north of Bakersfield is to take Highway 99S to Bakersfield and then 178E to Lake Isabella, 155 to Kernville.