William Finnegan didn’t bring a surfboard to the Miami Book Fair despite the proximity and prominence of ocean coastline. But that’s only because the placid waters of South Florida lack the scope and intensity of the furious waves Finnegan has surfed most of his life, which form the basis of “Barbarian Days: A Surfing Life,” (Penguin, $27.95) his critically acclaimed memoir.

For Miami, he’s traveled light.

“No board,” Finnegan said with a hint of resignation.

Finnegan, who is better known for his reporting on wars and global politics as a staff writer for The New Yorker, reached into his past for an autobiographical look at how surfing shaped and guided his being, from the moment he first stepped on a board as a youngster in California, to his years growing up in Hawaii and ultimately to his globe-wandering quests to isolated locales in search of challenging waves.

What resulted was not so much a book about surfing but about life itself.

A cadre of friends – male and female – are along for most of his “surf odyssey,” which took him to remote countries and island outposts, far distanced from the beaten path of civilization.

To make the book work for a wide audience, Finnegan combined his intimate knowledge of a largely unfamiliar sport with his immense writing talents to create a 447-page book that reads shorter.

“It’s a hurdle to tell surfing stories and make surfing sort of come alive for people who don’t have any interest in it,” Finnegan said. “I really worked to make it interesting for non-surfers. I didn’t think of it entirely as a book about surfing.”

Based on the feedback, Finnegan feels he succeeded.

“I’ve had a lot of readers say it’s not about surfing, which I love to hear,” he said. “It’s about men. Or love. Or obsession. Or how to live.”

The inspiration was a two-part, 40,000-word piece he wrote for The New Yorker about surfing in San Francisco. Finnegan said he spent seven years writing the story, which was published in 1992. Finnegan’s publisher liked it so much she asked if he could expand it into a book.

Finnegan balked at first.

“If I was going to do something about surfing, it would be about something different,” he argued. “It would be about other places and other people. This might be a chapter. She said, ‘Great, write that book.’ ”

That was 20 years ago.

Writing a memoir was a new challenge for Finnegan, and he said it’s not as easy as it might seem at first glance. After all, he was digging back to his youth (he is 63), re-creating conversations and events that took place decades ago, describing individual waves – and there are plenty that he describes – in precise detail.

“A memoir is a very weird genre for a reporter,” Finnegan said. “Imagine. You end up investigating your own memories, reporting on your past, and you’re not the only interested party. These are private lives we are talking about. Nothing [was] on the record. And you give yourself license to depict all these old friends and loved ones and these shared, unguarded moments, usually many years later. And that’s a big irrigation.

“It turns out that some of your most vivid memories are mistaken as you go back to do some research and realize that you (remembered) it wrong.”

Finnegan received help from a former friend and girlfriend, who had saved his letters – now decades old – and who kept their own journals of their times together. Another friend had saved all the detail-rich letters Finnegan mailed to him during his surfing days.

“I remember very few individual waves,” Finnegan said. “That’s nearly 50 years ago. But I had this amazing cache of letters that were returned to me by my best friend, a huge stack of letters. I opened them up and think, ‘Oh my God. 1966. 1967. Endless, numbing detail about each wave.’ They were a gold mine.”

Finnegan kept his own journals but said they weren’t as illuminating.

“My journals are not full of elaborate descriptions,” he said. “Usually, I was writing about how my girlfriend was driving me nuts or something.”

In the end, what “Barbarian Days” reveals is that the unpredictable and deadly-dangerous waves are always in charge, and that Finnegan and his mates are merely along for the ride, hanging on for dear life in some instances.

“You’re always happy when you get back to shore when you’ve been scared, but it’s not my favorite part of surfing at all,” he said. “What I’m after – in heavier waves, bigger waves, hollower waves, more intense waves – is really an experience of beauty. It’s this really sort of drenching experience of beauty that you’re after.”