Big Tree at Calaveras Big Trees State Park

If you have neck problems, don't visit Calaveras Big Trees State Park, home of some of North America's largest trees, because you will be spending your trip looking upward at the phenomenal Sequoia redwoods. This photo is taken on the popular North Grove trail, near the park's entrance.

If you go, visit Calaveras Big Trees' official site.

Unnamed Waterfall in Russian Gulch State Park

Maps simply refer to this waterfall in Russian Gulch as "waterfall," but I wish I knew its proper name because it is a refreshing end to a peaceful, shaded stroll on the Fern Canyon Trail. The first part of the trail can be biked, but the last mile or so can only be hiked. A group of picnic tables provide a pleasant rest stop midway through the trail. The total round trip is about 6.5 miles depending on where you park your car, a bit far for our then 4-year-old son to walk, but we misheard the ranger and thought "just over three miles" was round trip, not one way. Needless to say, we carried him piggyback most of the trek out. 

For your reference, here's the California State Park Department's description of the trail and a map of the location. If you go, wear layers and don't forget mosquito repellent.