Background: The weekend of 4th of July rolled around, and the idea of Lake Tahoe didn't appeal to me.  Not that its a bad place to visit, with water clarity so high the bottom is visible, but its where everyone in the Bay Area goes for a weekend getaway.  Solution: Shasta Lake, the lake formed by Shasta Dam restraining the Sacramento River, about a four hour drive north of San Francisco.  Under each photo, I write my personal reflections...  
  

Related Itinerary:  Sundial Bridge, Shasta and Crater Lakes, July 2013: Day 1, Day 2 

If you're looking to do some sightseeing on a short road trip, I think this itinerary is more than sufficient.  However, if your goal is to really explore the outdoors, this itinerary may be a bit scanty.  I'm not qualified to give advice to hardcore outdoorsy people, but here's some stuff I didn't do that others may enjoy.  I also write some general tips about visiting Crater Lake National Park.  

Summary: We drove from Medford, OR to Crater Lake early morning, where we spent the day before driving back to San Francisco - so a pretty long day.  The activity level was light as most sightseeing involved driving from vantage point to vantage point in the national park.  The only strenuous activity was the Watchman's Peak Trail - totally worth the effort.  

Summary: The first day in a two-day 4th of July trip, we drove from San Francisco, CA to accommodation in Medford, OR.  Along the way we saw the Sundial Bridge in Redding, CA and rented a boat on Shasta Lake in Shasta Lake, CA.  Both are along Interstate-5 between San Francisco and Medford.  The Sundial Bridge is literally a sundial and its shadow tells the time of day pretty accurately.  Shasta Lake is the reservoir of Shasta Dam, and offers many water activities amidst gorgeous views.