Avenue of the Giants is a great alternative to the freeway/highway. Best part is there are multiple opportunities to hop back on the freeway once you've had enough of the trees, which didn't happen for me!
We really enjoyed the Founder's Grove. Very easy hike with numbered stops on a brochure filled with information. We also followed the driving route signs. You can get a map and information in a box right as you exit the freeway. There is a visitor center right in the middle of the drive which is worth a stop. Good, small exhibit area.
This was a great introduction to the lovely redwoods groves we encountered in the National Park further up the coast.
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