Steered by his 19th-century Appleton's guidebook, Michael Portillo embarks on a one thousand-mile American adventure through California. Along the way he discovers how the railroads conquered the wild landscapes of the west and how California became America's richest state. Beginning in the Silver State of Nevada, Michael takes to the skies over the dramatic Sierra Nevada mountain range. At Lake Tahoe, he hears of the first European explorer, known as 'The Pathfinder', whose discovery opened up the west for settlement.

Travelling on the historic Virginia and Truckee heritage line, Michael investigates the vast deposits of silver and gold ore on which Virginia City was built. At Chollar Mine, he finds out about the short-lived mining boom and meets a quirky relic of the period - the pistol packin' preacher. Crossing the border into the Golden State of California, he ascends the 7,000ft granite cliffs to the Donner Pass where ambitious plans to carve a rail route through the rugged terrain were made a reality by Chinese immigrant labourers. In Colfax, Michael swaps his customary iron horse for the real thing and saddles up for a lesson in cowboy dressage. At Sutter's Mill, close to Sacramento, Michael pans for gold at the very spot that triggered the 1848 gold rush and enjoys a saucy show at California's first public theatre.

Venturing underground, he discovers how the streets of Sacramento were raised following the Great Flood of 1862 and visits the $900 million dam under construction to improve the city's flood defences. It is a first for Michael in the kaleidoscopic sweet factory of an iconic American confectionery brand that traces its roots to the 19th century. And, taking a cue from his guidebook, he samples the fruits of the Napa Valley in a gourmet lunch on board the Napa Valley wine train.