Midway down East Division Street, a family of four has paused on the sidewalk. Dad has the look of a man who would rather be elsewhere, but mum is smiling gamely, projecting a convincing air of fascination. Yet it is the two girls – somewhere in their early teens – who are most enthralled by their surroundings. Indeed, one of them squeaks in delight as she stares at the white clapboard house opposite, reaching quickly for her camera phone.
To the uninitiated observer, this might seem odd. The property in question is the Miller Tree Inn, a pleasant bed-and-breakfast bolthole on this unassuming American avenue. But the giveaway is the big image of Robert Pattinson, which gazes – red of eye, chalky of complexion – from an upstairs window. The younger daughter emits another squeal.
Here is the Twilight effect in action. For this, of course, is Forks, the little town that won the Hollywood lottery. Wedged into the far north-west corner of the US, 130 miles west of Seattle on the Olympic Peninsula (the thickly forested promontory that rears up as the last hurrah for Washington State), this tiny speck on the map was largely unknown until the novelist Stephenie Meyer set her stories of lovelorn teenage vampires and schoolboy werewolves in its remote streets. When the movie industry latched onto the Twilight saga (the first film was released in 2008, the fifth and final instalment, Breaking Dawn – Part 2 was released on Friday) Forks was shoved, blinking, into the spotlight.
For the last half-decade, legions of fans have flocked to the town hoping to peer into the lives of the three main characters – the vampiric Edward Cullen (Pattinson), the lupine Jacob Black (Taylor Lautner) and the object of their affections, Bella Swan (Kristen Stewart).
The surge in visitor numbers has astonished the town. "The Twilight effect has boosted tourism in Forks by 1,000 per cent," says Rianilee Belles, who offers guided trips around the key sites through her company Twilight Tours in Forks. "Interest tends to tail off a little between movies, but it will soar again with Breaking Dawn – Part 2."
What makes this travel craze all the more remarkable is that scarcely a second of the five movies has actually been shot in Forks (most scenes were filmed in British Columbia and Oregon). Indeed, the Miller Tree Inn, despite marketing itself as "The Cullen House", concedes this fact on its website. "Though it looks nothing like the movie version, our inn closely matches Stephenie Meyer's description of the Cullen family house," it confesses.
But, while it is understandable that a hotel might seize a golden opportunity, I am more intrigued to see that the rest of Forks has also embraced the phenomenon. At 775 K Street, a sign hammered into the lawn brands the property as "Home of the Swans." The police station boasts a Twilight display. And Leppell's Flowers and Gifts, once a simple florists, is one of several stores that now devote a considerable amount of floor space to souvenirs.
"When Twilight happened, it was a breath of fresh air for the town," owner Charlene Leppell tells me. "It can get busy at times, when we have three weddings and a funeral to prepare flowers for, and the shop is packed with Twilight fans. But it's great."
On the exterior of the Chamber of Commerce, a sign betrays the true cause of Forks's elevation to celebrity, recording that it receives 120 inches of rain every year. Meyer had not seen the town when she started writing, but selected it as her central setting because such deluges make it one of the dampest – and most atmospheric – locations in America.
The weather blesses Forks with portentous skies, perfect for yarns about juvenile blood-sucking. But it also dresses the town – and the countryside around it – in leafy verdancy.
And here is the real reason to visit this lonely patch of the USA. The Olympic Peninsula is a dramatic slice of wilderness, huddled at the end of the line for the American nation. It is craggy and tree-laden, the 6,900ft Mount Olympus rearing up (as any mountain with this title should) at its heart, the Olympic National Forest coating most of the interior. When I stroll in the dense pocket of the Quinault Rain Forest, 60 miles south of Forks, the congested branches arch overhead so keenly that, in parts, they block out the heavens.
This idea of distance – of a place on a limb – is exacerbated by Cape Flattery. The most north-westerly point of the contiguous USA lurks 30 miles above Forks – though the journey is closer to 60 miles by road, Route 112 meandering unhurriedly along the Strait of Juan de Fuca, the neighbourly bulk of Canada's Vancouver Island visible on the far side of this silver-blue channel. The Cape itself is reached via a mile-long trail where tumbled pine needles cushion each footfall. When I re-emerge at the water's edge, I am greeted by the sight of the Pacific in all its blank magnificence, reaching for the horizon.
Indeed, the seafront is arguably the Olympic Peninsula's grandest asset. This is the same American flank that flirts with the sun in California, but here is a decidedly different west coast, the sand grey, damp and sullen. Ruby Beach, 20 miles south of Forks, has a name that sings of jewellery. But, dominated by a huge bluff, torn from the landmass and dropped into the surf, it has an ambience that is more lost world than light and sparkle.
Forks, too, has its secret coves. On the adjacent Quileute Reservation – the home of Lautner's Native American wolf-child – La Push Beach is split into segments. Of these, Second Beach is the most glorious, accessed by another one-mile path between colossal cedar trunks. The shingle is littered with fallen giants, arboreal corpses rejected by the ocean and returned to sender as driftwood. The resulting scene is raw and achingly beautiful – and will remain so long after the final teenage vampire has discovered a new obsession.
The only non-stop flights from the UK to Seattle are on BA (0844 493 0787) from Heathrow.
Miller Tree Inn, 654 East Division Street, Forks (001 360 374 6806, millertreeinn.com). Doubles start at $115 (£72), including breakfast.