Get a big dose of Vitamin D on this 13-mile overnight loop in Austin Creek SRA, where grassy, oak-dotted hills soak up spring sunshine while Sierra summits still rest under snow. The open terrain invites an early wildflower show—lupine, irises, and buttercups line the park’s 20 miles of trail starting in April—yet hikers are few (most head for Austin Creek’s better-known neighbor, Armstrong Redwoods State Reserve). Visit both parks with a season-starter (or winter treat)that sets the bar high for the rest of the summer: Beginning at the Armstrong ranger station, follow the Pool Ridge Trail on its northward course among 250-foot-tall redwoods. Hike west on the Gilliam Creek Trail, which scales grassy hills and hugs glittering, fern-lined streams, then, at mile 6, take the East Austin Creek Trail, a fire road, 2 miles to Mannings Flat Campsite ($25 permit required) to end an 8-mile first day. This shaded, east-facing nest sits on a bench above Austin Creek and offers easy access to its azure pools (which make fine swimming holes when temps allow). Day two, hike east for 5 miles on the forested East Austin Creek Trail, which includes a mile of steep climbing (gaining 1,000 vertical feet), to return to your car.
Info Drive time from San Francisco 1 hour, 40 minutes