Sequoia & Kings Canyon National Park
http://www.nps.gov/seki/index.htm
There are many trails that connect the Sequoia groves.
http://www.sequoia.national-park.com/hike.htm
Besides the Giant Sequoias, there is a rare marble cave in the park (most caverns are limestone). Crystal Cave is accessed by a picturesque trail that leads to the Merced river valley.
http://www.sequoiahistory.org/cave/cave.htm
Moro Rock is a fantastic view.
http://kevingong.com/Hiking/MoroRock.html
http://en.wikipedia.org/wiki/Moro_Rock
Enter the park from the south, CA Route 198. It doesn't allow RV's or trailers so there is less traffic. It's a mountain road that climbs thousands of feet, has great hairpin turns and the views are spectacular.
http://maps.google.com/maps?q=merced+map&ie=UTF8&split=0&gl=us&ei=CGyMSt3lMIiksgPG5oi4CQ&ll=36.486453,-118.875504&spn=0.422878,0.447693&z=11
There is lodging at Three Rivers, CA and it is close to the entrance.
http://maps.google.com/maps?sourceid=navclient&rlz=1T4HPIA_enUS314US314&um=1&ie=UTF-8&q=three+rivers+ca+lodging&fb=1&split=1&gl=us&view=text&ei=9m2MStz2LIWQsgP137S1CQ&sa=X&oi=local_group&ct=more-results&resnum=1