Passing a photogenic coastline and the kind of suburbia that gives town-planners a bad name, the journey between Los Angeles and the border town of San Ysidro crosses the state’s most heavily populated region.

A fast route (Interstate 5, known as I-5) is a godsend to anyone itching to test his or her driving skills and temper on California’s busiest stretch of six-way freeway. Tailbacks permitting, I-5 whizzes above the tract housing and shopping malls of Orange County, a vast middle-income dormitory of Los Angeles, and continues to the slightly less homogenized hinterland of San Diego, California’s second-largest city.

For some, I-5 begins and ends with a trip to Disneyland, the theme park about which everyone has an opinion but in which few visitors ever fail to enjoy themselves. Another of the best places to visit on I-5 could hardly be more different: the mission at San Juan Capistrano, a mix of haunting ruins, lush gardens and impressively-restored buildings that serve as a reminder that the Spanish had a toe-hold here long before Mickey Mouse showed up.

Just south of San Juan Capistrano, I-5 combines with our medium route, Hwy-1, a two-lane road following the coast and linking the shoulder-to-shoulder settlements south of Los Angeles, varying from the surfer-packed Huntington Beach to the millionaires’ lair of Newport Beach. Hwy-1 also, albeit intermittently, reveals landscapes of rugged beauty to rival those of the state’s central and northern coasts.

Bizarrely, though, you need to cross a vast military base – which I-5 does-to really see how the southern coast looked before the property developers arrived. From the base, I-5 speeds towards San Diego, but branch off on our slow route (Hwy-21) and you’ll discover a string of small coastal towns north of San Diego, including the exquisite La Jolla, which can brighten anyone’s day.

The weather in this region is welcoming year-round, but expect to pay extra per night for accommodation if you’re passing through during the summer.

TRANSPORT

With more than 10 services a day, AMTRAK’s Pacific Surfliner (www.amtrak.com) runs between Los Angeles and San Diego (where you continue to San Ysidro for only 25 mins) is the busiest in the state, and much of the route is a scenically appealing coastal run. Greyhound bus connections are good too (www.greyhound.com), if less pleasing to the eye. Some buses, except the non-stop express services between Los Angeles and San Diego, call at Anaheim and Oceanside.