It is what might be described as a Lebowskian moment. By some cosmic coincidence, the International Surfing Championships are taking place off the famous Shell Beach just as Bridges - the man who reached a whole new generation of fans as the perpetually stoned surfer, "Dude" Lebowski, in the Coen brothers's The Big Lebowski - arrives in town to accept a lifetime achievement award at the San Sebastian film festival.
"I feel a great warmth for Spain. Unfortunately, I don't consider myself much of a traveller," says Bridges, stretching out in an impressively crumpled shirt and chinos on a baroque sofa. "I travel a lot in my work and I have a hard time turning the old clock around these days."
And these days, with long flowing grey hair and a full beard, he seems a long way from the clean-cut, devilishly handsome millionaire who seduced defence lawyer Glenn Close in 1985's Jagged Edge. But at 54, Bridges retains a boyish enthusiasm and an amiable, ambling aura, that devastating smile shining like a beacon from below a thick foliage of hair.
Born and raised in California, he is a flower child of the Sixties, and maybe it's the surfing references or a certain facial resemblance, but I have a sudden vision of Bridges as Brian Wilson, the Mozart of pop who flew too close to the white-hot sun of creativity. If there was ever a biopic of the Beach Boys' beached idol, then Bridges would be the perfect candidate for the lead role.
As they say in The Big Lebowski, here is "a guy whose casualness runs deep", and Bridges' public image is now inextricably linked to el Gran Lebowski, the essence of Olympian slackerdom. Even the Dude's clothes - loose Hawaiian shirts, bathrobes and drawstring trousers - came from Bridges' own wardrobe.
In his latest film, he is back in kaftans and loose clothing, playing an author in The Door In The Floor - Tod Williams's freakishly cold and insipid adaptation of the first section of John Irving's novel A Widow For One Year - flapping around the autumnal lawns of a sad Hamptons house in flowing robes and sandals like some Long Island Testament prophet.
It's as if Bridges was beginning to specialise in playing men who have lived life to its bohemian full and retreated into zen-like indolence and a kind of contented depression, looking out at the raging world with a quizzical eye and a slightly worried smile.
In Bridges' case, the lifetime achievement award seems more than justified. He has made close to 60 films (for someone who declares he is lazy he works constantly), some of which were key moments in modern American cinema, ranging from the young buck prodigy in The Last Picture Show in the Seventies to The Fisher King and Fearless in the Nineties.
Bridges' star burned bright early on: he earned a best supporting actor Oscar nomination for The Last Picture Show at the age of 21. He was nominated again in 1975 as the boy drifter opposite Clint Eastwood in Thunderbolt and Lightfoot, and later twice more, for Starman in 1985 and The Contender in 2001.
Though he has never won the elusive golden statuette, it's not a bad record for a man who originally planned to be a painter and thought long and hard before following his father, Lloyd Bridges, and brother, Beau, into acting. "There are a lot of people who have been instrumental in my so-called success," he says, "a lot of wonderful artists and directors, but my family is the main reason I am where I am."
He met his wife, Susan Geston, while making Rancho Deluxe in 1975 - making theirs a marriage of near unique longevity by Hollywood standards. She was a student waitressing in a Montana diner and he was smitten, then crushed when she initially turned down a dinner date. He still has the Polaroid pictures to prove it. They married in 1977 and have three daughters, Haley, Jessica and Isabelle. But will he follow his father's lead and encourage them into the business? "Let's see, my youngest is 10 and the other girls are in their 20s," ponders Bridges. "But they haven't shown any inclination to go to acting yet. I dunno, it's kind of open, I guess."
Although he can appear a little vague, Bridges is one of the most refined actors and likeable men in the film business, often playing seemingly attractive characters with hidden misanthropic tendencies. In The Door In The Floor, he plays a children's author who tries to break his wife's frigid limbo - a result of the death of their two boys in a car crash - by manoeuvring his 16-year-old assistant into her bed.
"I'm a fan of John Irving's writing; the way he juggles the comic and tragic seems very real to me," says Bridges, "This story is about how people deal with the tragedy in different ways. In a way, each parent holds the other responsible for the loss of their sons."
It is a curiously deadening drama about the personal and emotional fall- out of calamity. Kim Basinger is entirely static as Marion, the beauteous wife dipped in aspic, and Jon Foster tries hard as the virginal young assistant. But Bridges rules every scene as a philandering artist, full of sleek betrayals and a disregard for his wife's deep depression, his charming facade flaking and peeling as we watch.
"I love going to the movies and I love being surprised," says Bridges, "so I gravitate towards characters who are a little off-centre, who are not quite what you expect; that's what I'm attracted to."
Strangely ineffective as a straightforward action hero, (see - or don't, for that matter - Blown Away), he is best in ambiguous and contradictory roles, where the beatific smile masks deep psychological fissures. The entire premise of Jagged Edge was based on that conceit, the handsome profile hiding a seething pit of psychotic malevolence.
Bridges' own image hides a more complex reality - though a rather happier one. He may gleefully promote himself as an indifferent slacker, but he's a Hollywood renaissance man with a highly regarded photo gallery of behind-the-scenes portraits from his films of the last 20 years. In addition, he is an accomplished painter, piano player and guitarist with a couple of playful albums under his belt. Above all, he makes acting seem as easy as falling off a surf board. "The thing I learnt most from my father was his approach to the work," says Bridges. "He took great joy in this work, and that was contagious. On the set people respond to that; they do better work. I try to have that same joy, spread it around a little. Acting's only make- believe, after all."
But he works at it, reviewing daily videos of his performance during the filming of The Big Lebowski; studying avionics and the testaments of air crash survivors for Fearless; obsessively practising jazz piano for The Fabulous Baker Boys and going into rebirthing techniques and dance for his part as an alien getting used to the human body in Starman.
"I don't separate the leading man roles from the character roles, I don't make that distinction," he states. "I consider so-called leading man roles as another character to play. And I look for characters who have a lot of layers, like in Fearless and The Fisher King."
His father Lloyd, who died in 1998 at the age of 85, remains a massive influence. " He encouraged his kids to go into showbusiness, he loved it so much. He taught me all the basics: how you always play a scene like it was the first time, how to let what the other actor is saying form your response, how to be part of scene and live it. All of it came from him."
After 35 years as an actor, painter, musician and photographer, would he consider moving into film directing? Bridges thinks for moment, eyes drifting to those Atlantic rollers outside. "I may end up directing one day," he replies with a slight sigh, "but it takes up so much of your life. It's a tough call, and, like the Dude, I have my lazy side."
`The Door in the Floor' is on general release from today