North America is, of course, all about the road trip, nowhere more so than in California where, if you put your foot down, you can go from balmy beaches to snow-capped mountains to unrelenting desert in the space of a day. But there's a lot to be said for staying within the speed limit and really looking at the landscape. The Pacific Coast Highway between Los Angeles and San Francisco is one of the most stunning drives in the world, taking you out of the city and deep into the wilderness, with the ocean glistening over your shoulder.

Admittedly, for the first leg of the journey you may wonder what all the fuss is about. Emerging from the smog-filled haze of Los Angeles and the manicured mountains of Malibu, we hit the seaside resort of Santa Barbara, according to our guidebook "the home of the newly wed and the nearly dead". We saw no reason to stop. Instead we refuelled at the pleasantly picturesque mission town of San Luis Obispo, the halfway point between LA and San Francisco, and where the road rejoins the sea. As you inch north, shopping strips and suburbs are slowly replaced by the more elemental charms of nature, though the really spectacular scenery doesn't start until you reach San Simeon, home to a burgeoning colony of elephant seals and Hearst Castle, the hilltop estate of the newspaper magnate William Randolph Hearst. The word kitsch doesn't quite do justice to this wedding-cake construction, though the line-up of coaches outside swiftly wiped the smiles off our faces and sent us scurrying back to the car.

On, then, to Big Sur, where Highway One shrinks to two lanes full of hairpin bends and treacherous drops to the sea. This is an area of outstanding natural beauty that combines dramatic mountain ranges, giant forests of sinewy redwood and barren coastal scenery. Jack Kerouac came here to escape his clamorous fans, and ended up writing a book about it. The road is dotted with look-out points where you can fully appreciate the coastline's primal beauty without fear of plunging to your death. In the spring, you're likely to spot the spouts of grey whales on their way back to Alaska.

Venture inland amid the firs and redwoods on one of the many woodland trails and you will feel like the only being on earth. The Pfeiffer State Park has it all - vast mountains, cascading waterfalls and abundant wildlife including deer, foxes and raccoons. Nearby Pfeiffer Beach, with its turquoise waters and sculptural granite outcrops, is one of the most photographed beaches in the world. Basking in the silence, it's hard to imagine that Silicon Valley is just around the corner.

Seclusion - or at least the illusion of it - is the key to this extraordinary stretch of California coast. Certainly, there are relatively few buildings to disrupt the idyll that is Big Sur. The town itself is unremarkable, a small strip of motels, restaurants and gas stations. The more upmarket resorts are situated further out of town and are blended sympathetically into the landscape. We spent the night at the Post Ranch Inn, a sybaritic retreat perched on a wooded ridge right above the ocean. The inn comprises 30 designer log cabins, facing toward the sea or the forest depending on your preferred view. The ocean houses are smothered in topsoil and planted with grasses and wildflowers while the stilted tree houses sit high amid the branches. Each cabin has an open fire and a sunken slate bath big enough for two. Before dining in the glazed cliff-top restaurant, we sat on our private terrace breathing in the salty air and watching the sun melt into the sea. Later on, a Mexican astronomer talked us through the constellations.

Waving a reluctant goodbye to the Post Ranch Inn the next morning, we rejoined the highway to the town of Carmel, where Clint Eastwood was once mayor, past Watsonville, where the future Marilyn Monroe was crowned Artichoke Queen, and on to San Francisco, our final destination. There, at the foot of the Golden Gate Bridge, we were able to pay our respects to the sea one last time. Strangely, it wasn't quite the same.

Post Ranch Inn, Highway One, Big Sur, CA 93920, 00 33 831 667 2200,