Highway 120 will be the best way to approach Yosemite if you are coming from the big cities of San Francisco or Sacramento and their major airports. This scenic route skirts around the Northern edge of Mariposa County and passes through the lovely towns of Buck Meadows and Groveland. Highway 120 is mostly straight or gently curving, except for the 8 mile Priest Grade ascent which will gain over 1,000 feet of elevation in 8.5 miles.
The largest town on the route is Oakdale, which is a good place to stop and stock up on groceries and fill up on gas. Groveland is also a lovely place to take a break from driving and check out the oldest saloon in California.