Standing at the foot of a coastal redwood is one of life's great humbling experiences. It's not just that it's the planet's tallest living thing (the highest known specimen is seven storeys taller than the Statue of Liberty). Or that it can live for 2000 years. It's the awe-inspiring realisation that the rust-red giant towering above you came from a seed slightly bigger than a pinhead.
Millions of years ago there were redwoods all through North America, Europe and Asia. Now, you can only find them in a narrow 720-kilometre coastal strip from central California to southern Oregon. Before the timber-hungry California gold rush of the 1850s, it is thought there were more than 800,000 hectares of original "old growth" redwoods. Now less than five per cent of that remains. Thankfully, most of what is left is protected by state parks – more than 90, in fact, stretching from San Francisco up to the Oregon border. Throw in some stunning coastal scenery, fascinating pioneer history and superlative food and wine, and you've got one of America's most memorable road trips.
This year is a particularly good one to tackle it because the Save the Redwoods League is celebrating its centenary by providing free access to more than 40 state parks on the second Saturday of every month (see freeredwoodsdays.org). Here are some of the highlights.
MUIR WOODS NATIONAL MONUMENT
San Franciscans are blessed to have a protected forest of old growth redwoods just 16 kilometres north of the Golden Gate Bridge. Muir Woods contains 97 hectares of redwoods, many of which soar to more than 75 metres. The park has 10 kilometres of trails, ranging from easily-accessible boardwalks that meander along the valley floor to more challenging hikes that scale the hillsides. Interestingly, it was the first national park to recognise the importance of quietness and visitors are encouraged to observe this while looking around Cathedral Grove, the reserve's most spectacular stand of trees.
Of course, Muir Woods' proximity to San Francisco is both a blessing and a curse. With about a million visitors a year, the park can get unbearably crowded, particularly at weekends. A parking and shuttle reservation system was introduced in January so book ahead and try to arrive when the park opens at 8am.
DETAILS 1 Muir Woods Road, Mill Valley, California. Open daily, 8am to sunset. For fees and reservations, see gomuirwoods.com
DO Kids will love the park's junior ranger program and Redwood Discovery riddle quest.
STAY Located two blocks from Union Square, the chic 196-room Hotel Zeppelin combines San Francisco's psychedelic past with striking contemporary design. See viceroyhotelsandresorts.com
ARMSTRONG REDWOODS STATE NATURAL RESERVE
Want to lose the crowds? Simply drive north. Armstrong Redwoods is a magnificent 326-hectare reserve of primeval old-growth redwood forest in Sonoma County, 122 kilometres north of San Francisco. Follow the Pioneer Nature Trail and you'll stroll through groves of soaring, ramrod-straight trees, some clustered together in conspiratorial huddles, others cork-screwing around each other like amorous couples. What you won't see are many other people. During an hour-long midweek visit, I only passed two other hikers.
Notable specimens include the park's tallest tree, the 95-metre-tall Parsons Jones (named after local reverend William Ladd Jones), and the oldest, the 1400-year-old Colonel Armstrong (named after the park's founder Colonel James Armstrong, who, ironically, was a lumberman). Another noteworthy feature is the reserve's 1200-seat amphitheatre. Surrounded by soaring redwoods, it's the perfect place to sit and admire these towering titans.
DETAILS 17000 Armstrong Woods Rd, Guerneville. Open daily, 8am to one hour after sunset.
DO Soar through the treetops with Sonoma Canopy Tours, one of only two zip-line courses in a redwood forest. See sonomacanopytours.com
STAY Spend a night in the woods at Autocamp, a collection of luxury Airstream trailers in a redwood grove near Guerneville. See autocamp.com
HENDY WOODS STATE PARK
At only 330 hectares, Hendy Woods in Mendocino County is by no means the biggest state park in northern California. And with only two groves of old growth redwoods, it's also not the most impressive. What sets it apart is that it is one of the few parks that are wheelchair accessible. The one-kilometre Gentle Giants All Access trail winds through a majestic grove of ancient redwoods (many of which are more than 90 metres high), providing access for people who would otherwise miss out. Another reason to include it on your itinerary is that it's located within the Anderson Valley wine region, one of the state's premier producers of pinot noir and sparkling. If all that wasn't already enough, the redwood-lined drive from the valley to the coast along Highway 128 is nothing short of spectacular.
DETAILS 18599 Philo Greenwood Rd, Philo. Open daily, 8am to sunset.
DO Explore Mendocino's Big River Estuary in a beautifully constructed outrigger canoe made from re-purposed old growth redwood. See catchacanoe.com
STAY Located on a windswept bluff near Big River Estuary, Brewery Gulch Inn is an unashamedly romantic 10-room B&B built from salvaged redwood. See brewerygulchinn.com
HUMBOLDT REDWOODS STATE PARK
There's a reason why Humboldt gets all the redwood glory. Located 350 kilometres north of San Francisco, the park contains the world's largest expanse of old growth redwoods – a staggering 68 square kilometres. It's also home to more than 100 of the 137 known redwoods taller than 110 metres. Throw in the outrageously scenic Avenue of the Giants, a 50-kilometre drive that snakes through the heart of the park, and it's easy to understand its appeal.
You could spend days exploring Humboldt's 160-plus kilometres of trails but if you only have time for one stop, make it Founders Grove. Located at the north end of the park, it has an 800-metre signposted trail that takes you past many of the biggest trees, including the Dyerville Giant, a 110-metre monster that fell during the winter of 1991. It's often difficult to appreciate just how tall these trees are from the ground; walk the length of the Giant and you'll be left in no doubt.
DETAILS 17119 Avenue of the Giants, Weott. Park open daily, 24 hours. Visitor centre open 9am to 5pm, April to October; 10am to 4pm, November to March.
DO Indulge in the region's many redwood-themed attractions, such as the Chandelier Drive-Thru Tree, the One Log House and the Charles Kellogg's Travel Log (an RV hollowed out of a redwood). See drivethrutree.com; oneloghouse.com
STAY With more than 250 campsites spread over three campgrounds, the park is a great place to sleep among the redwoods. See www.parks.ca.gov
REDWOOD NATIONAL AND STATE PARKS
Humboldt used to have the tallest known living redwood – the 112-metre-high Stratosphere Giant. But in 2006 a group of scientists found three taller trees in a remote grove of Redwood National Park. They named the tallest one Hyperion ("The High One"), which tops out at a staggering 115 metres. The location of the grove has been kept a secret but there are hundreds of equally impressive examples in this cluster of four parks near the border with Oregon.
The biggest and most easily accessible trees are in Prairie Creek Redwoods State Park, a 5600-hectare reserve 80 kilometres north of Eureka. Take the Prairie Creek Trail from the visitor centre and you'll pass by many of the tallest specimens, including the 92-metre-high – but rather unimaginatively named – Big Tree.Interestingly, redwood forests don't support a lot of bird or insect life, which only adds to the cathedral-like sense of awe. Little wonder that in 1980 UNESCO designated the parks a World Heritage Site.
DETAILS Newton B. Drury Scenic Parkway, Orick. Open daily.
DO Tuck into a hearty feed at the Samoa Cookhouse, the last of the many family-style restaurants that once catered to the region's army of ravenous lumbermen. See samoacookhouse.net
STAY Stay in the heart of the park at Elk Meadow Cabins and wake up to herds of grazing Roosevelt elk. See elkmeadowcabins.com
FIVE MORE THINGS TO DO
Once a thriving Russian fur-trading base, this historic state park in Sonoma County is the site of California's first windmills and shipbuilding industry. See fortross.org
This 132-year-old scenic railroad passes through pristine redwood forests on its 64-kilometre journey from Fort Bragg to Willits. See skunktrain.com
Located in the heart of Sonoma County's wine region, this highly acclaimed new restaurant serves three variations of an 11-course tasting menu. See singlethreadfarms.com
POINT ARENA LIGHTHOUSE
Take a tour of the tallest lighthouse on America's west coast and admire a handmade, six-tonne first order Fresnel lens. See pointarenalighthouse.com
HOG ISLAND OYSTER COMPANY
Indulge in a feast of freshly shucked oysters at this bayside oyster farm in the tiny hamlet of Marshall, one hour north of San Francisco. See hogislandoysters.com
United flies to San Francisco from Sydney and Melbourne. Upgrade to Economy Plus for more leg room and quicker disembarkation. See united.com
Rob McFarland travelled as a guest of United, Brand USA, Hotel Zeppelin, Sonoma County Tourism, Visit Mendocino and Eureka-Humboldt Visitors Bureau.