Any of the major mountains make for a fabulous weekend getaway—particularly if you’ve got a three-day weekend to play with. Lake Tahoe  has numerous recreation options and is usually accessible all year long. Many California residents take even longer trips to Tahoe; one or two week vacations to this area aren’t uncommon because there’s so much here to see and do. Mount Shasta and Mount Lassen are far more remote; it takes several hours driving from Tahoe (or most anywhere else in the state) to reach either of these peaks.
Mount Shasta  offers fairly easy and reliable year-round access off I-5, plus both winter and summertime outdoor recreation. The weather on and near Shasta can get extreme; expect winter storms half the year and brutally high temperatures in the summer months. Check the weather reports so you pack the right clothes for your trip. If you’re planning to climb high up the mountain, be aware that it’s high enough to be create its own weather.
The best time to visit Mount Lassen , out in a remote eastern corner of the state where the weather gets serious, is the middle to end of summer. It can still be snowy on Lassen as late as June, so keep that in mind when you make your camping plans. During the winter the main road through the park closes, making your visit to the region far less interesting.
Don’t try to see all three mountains unless you’ve got a week or so to explore. If you do want to make a California mountains trip, start at Lake Tahoe  and make your way up Highway 395 to Susanville and then across to Lassen . Hit Redding  next, adding Shasta Lake  and Mount Shasta .