Getting the jokes was the key to my understanding of Ulysses. I realized I could skip — in the beginning, at least — the Homeric parallels, the Shakespearean references and the rest of Joyce's awesome erudition and simply go with the narrative flow, carried along by the vivacity, poignancy and humor of the prose. Joyce was praised as a genius and denounced as a pornographer after Ulysses was published in 1922, but he thought of himself more as "an Irish clown, a great joker at the universe." So I stopped trying to figure out Ulysses. The more relaxed I became about reading it, the better I understood it — and the greater was my desire to follow in Bloom's footsteps.

That's how I end up on Westland Row, the first stop on our walking tour. In 1904, the year in which the book is set, there was a post office here; today it's tucked into the corner of a busy train station. Bloom enters and the rest of us pile in after him, blocking all the exits and preventing access to a dry cleaner's shop. "Are there any letters for me?" Bloom asks nervously. The man behind the counter gamely plays along and hands him a crumpled brown envelope. It's a letter from Martha Clifford, with whom Bloom is carrying on an illicit, erotic correspondence. Just then there's a scuffle in front of the dry cleaner's; the shopkeeper is annoyed. But a tall, white-haired commuter intervenes. "It's Bloomsday," he booms. "Show a little respect for James Joyce!" We all erupt in a round of applause. Even the dry cleaner is amused.

From the post office, we travel south to Lincoln Place and Sweny's chemist, where Bloom stops to get some lotions made up for his adulterous wife, Molly. Sweny's is still in exactly the same spot it was in 1904 and the original sign still hangs above the door. Bloom places his order and makes an impulse purchase: a bar of lemon soap, one of the talismans he carries with him throughout the book. Leaving Dublin without some lemon soap would be like returning from Lourdes without holy water. So I make an impulse purchase of my own.

As we head west toward Grafton Street, I wonder why we do it. Why do we travel from all over the world to traipse around Dublin on Bloomsday? The answer is simple: Because Ulysses is such a great book. Bloom is a contemporary everyman, and his peregrinations encompass the whole of human life, from birth to death, high art to low lives, Catholic mass to masturbation. Joyce made Bloom's inner world so vivid that he seems real; for Joyceans, a trip to his home at 7 Eccles Street, now a hospital, provides the same kind of emotional kick that, say, an American history buff gets from visiting Abraham Lincoln's log cabin birthplace. The book becomes an obsession, something we might put aside for a while but which we never really stop reading. "Ulysses is the essence of literature, the finest novel of the 20th century," says Harriet Rosenman, who just retired as an English professor at Wilbur Wright College in Chicago. "It's been my dream to come here for years." Her husband made that dream come true as a retirement present.
By 2 in the afternoon, our merry band has swelled to around 500 people, all milling around outside Davy Byrnes, the "moral pub" on Duke Street where Bloom enjoys his famous midday repast — a glass of Burgundy and a Gorgonzola sandwich. I peel off from the tour at this point to pursue a more private pilgrimage.

"If I can get to the heart of Dublin," Joyce once said, "I can get to the heart of all the cities of the world. In the particular is contained the universal." There is one place in particular I have to see. It's off the tourist track, in one of the shabbier parts of town, an area of adult bookstores and boarded-up shops: 9 Little Britain Street, the site of Barney Kiernan's pub, now a hairdresser's. And just around the corner, on Little Green Street, across from E. McManus Fruit and Vegetable Merchants, is the spot from which Bloom ascends "to the glory of the brightness." I first saw this place from the platform of that Bamberg train station, but being here in the flesh feels like paying off an old debt, and earning a new blessing. After nearly 15 years of wandering through the maddening, mystifying, marvelous maze of Ulysses, it feels like coming home.