Redwoods are HUGE!!!
The redwoods are easily visited by driving up and down Avenue of the Giants road which runs right through the park. There are a variety of turnouts and parking areas, many of which feature trails with self-guided tours. The self-guided tours are usually short loops of about half or three-quarters of a mile long. There are a couple of places along the road which will let you drive your car through one of the trees (for a fee, of course).
The park contains the largest remaining old-growth redwood forest in the world. Some of the largest trees are here.
There are also some state-run camp grounds and a longer hiking trails in the park.
And the entire time I kept thinking I was on the forest moon of Endor. The redwood forest is so green and beautiful that it reminded me of the scenes from that famous movie. I later learned that parts of "Star Wars: Return of the Jedi" were indeed filmed in this park.