From optical illusions to unusual petting zoos, the famous Pacific Coast Highway has plenty of oddities worth pulling over for.

The road runs from Leggett in Mendocino County to Dana Point in Orange County and offers spectacular ocean views and cliffside driving along its more than 2650-kilometre length.

Commonly known as California State Route 1, the trip usually takes several days and covers everything from temperate rainforest to near desert. But there’s more, oh so much more.

Roadside attractions

These have been an integral part of the American road-trip experience since the get-go. In the early days of long-distance motor travel, enterprising folks with a talent for art and construction began building giant statues of everything from fruit to ducks to pull over and take a look – and spend some money.

While colourful structures are common in flatter parts of the interior US, many such spots found along the Pacific Coast – such as the drive-through redwood trees found in Leggett, Klamath and on the Avenue of the Giants – are somewhat integrated into the natural environment.

Others, such as the Mystery Spot in Santa Cruz and Confusion Hill in Mendocino County, rely on the use of optical illusions to draw in the crowds.

The Avenue of the Giants is, quite literally, unmissable. Photo: Unsplash

Modern stops

While roadside attractions aren’t being built at the same rate that they used to be, they still pop up from time to time, sometimes by accident. In fact, one of the newest roadside attractions on the Pacific Coast Highway – the Cardiff Kook Statue in Encinitas – wasn’t initially intended to draw gawks and groans.

This 1.8-metre-tall sculpture, which depicts a man on a surfboard, was initially intended to be a simple nod to the city’s surf community. However, when the statue was unveiled in 2007, local surfers were less than impressed, critical of everything from the statue’s surfing form to his proportions.

As a response, pranksters began dressing the statue up in costumes inspired by everyone from Elvis Presley to former US Supreme Court justice and feminist icon Ruth Bader Ginsburg, and now you’ll never be sure just how the famous surfer will be garbed when you visit.

Architectural oddities

Some of the weirdly wonderful spots along the route weren’t necessarily meant to make people stop and take a look, but they’re still worth a pit stop to see. In La Jolla, Sunny Jim’s Sea Cave beckons, daring visitors to descend 145 steps into a sandstone cave tunnel that served as the former residence of engineer and artist Gustav Schultz.

At the California Polytechnic State University in San Luis Obispo, the Architecture Graveyard is another worthwhile stop. Here, more than two dozen student-built structures sit in various states of disrepair; the oldest date back to the mid-1960s.

Roughly 65 kilometres up the road in San Simeon, Hearst Castle merits at least a few hours. This opulent landmark mansion, now managed by California State Parks, was built over a period of nearly two decades and features grand halls (some look like they were plucked from mediaeval Europe) and sprawling courtyards filled with fountains and statuary.

On the North Coast, the Sea Ranch Chapel is considerably less grand, measuring roughly the size of a small American garage. Still, its colourful stained-glass windows, sweeping roof and carved wooden interiors make it worth a stop, particularly if you’re interested in seeing an example of the Sea Ranch community’s signature architecture style.

Bioluminescent waves

Go for an evening walk along a Southern California beach in the summer and you may notice a mystical glow on the ocean waves.

What you’re witnessing is bioluminescence, a natural phenomenon that occurs when there’s a large population of plankton known as dinoflagellates present.

When waters are disturbed (such as by the force of the ocean or the swish of a kayak paddle), these emit a star-like shimmer that illuminates the waters around them.

Pacific Highway music

Pacific Coast Highway by the Beach Boys Leave it to the most California-centric band ever to pen a song about Highway 1.

Pacific Coast Highway by the Hip Abduction This PCH-themed song, featuring songwriter Trevor Hall, covers the road from Los Angeles up to the redwoods in Humboldt County.

Bixby Canyon Bridge by Death Cab for Cutie The narrator of this melancholy tune travels from San Francisco to Big Sur’s most famous bridge.

This is an edited extract from Journey Pacific Coast Highway by Lonely Planet, $36.99 RRP. Contact shop.lonelyplanet.com