The paved climb to Onion Valley Campground is one of three brutal road climbs outside of Lone Pine, California. The gradient is rather steady and steep, with some beautiful switchbacks that make for beautiful photography that would make Ansel proud, if you frame it right.
From the valley floor off Hwy 395 in Independence, the climb starts immediately. It is optically deceiving, but before hitting the base of the mountain you have already knocked off a huge chunk of the climb, then the switchbacks start. Enjoy from there, the fun stops where the road terminates at the campground.