The Milan-San Remo buzz truly starts on the eve of the race when crowds of respectful tifosi greet the Giants of the Road for pre-race formalities in the hallowed courtyard of Milan’s medieval fortress, the Castello Sforzesco. The Italian fans see the modern superstars, the Cancellaras, Cavendishes and Gilberts, as mingling with the spirits of the greatest Italian legends, Coppi, Bartali and Girardengo. And many of the cognoscenti hope that their country’s latest messiah, Vincenzo Nibali of Liquigas-Cannondale, can join those former champions, who all arrived triumphantly in San Remo multiple times.

But whoever wins the first of this year’s monumental classics, they know they’ll be joining a golden list of champions that dates back to 1907. And like all of this Saturday’s 200 starters, the winner will know he has overcome one of the harshest tests he’ll face all year. This seven-hour marathon, whose finale is raced at the speed of a track race, is rarely decided until the very last moments in often-dramatic fashion.

The past three editions have each ended unexpectedly. Last year, Aussie dark horse Matt Goss stunned a small breakaway to sprint home ahead of Fabian Cancellara and Philippe Gilbert. In 2010, it was the underestimated veteran Oscar Freire who dashed clear of a 25-man group to beat Tom Boonen and Alessandro Petacchi. And in 2009, Heinrich Haussler looked to have the race won until Mark Cavendish closed a massive gap in the final 100 meters with a phenomenal sprint to win by inches.

Such close finishes are among the many reasons why the Italians call Milan-San Remo La Classicissima, “the classic of classics.” Besides being the first major one-day race of the season, it’s more anticipated than any other, partly because it’s the classics season opener and also because of its prestigious reputation. The fans’ already heightened expectations are raised another few notches by the presence of the world’s best riders—not just the classics specialists, but also the riders who shine in stage races and grand tours.

It’s not a coincidence that La Classicissima’s most prolific winners include Giro d’Italia and Tour de France champions Eddy Merckx (seven wins), Costante Girardengo (six), Gino Bartali (four) and Fausto Coppi (three), who account for 20 victories in Milan-San Remo. Conversely, the sport’s best road sprinters also figure large in the race’s palmarès, with Freire, Erik Zabel, Mario Cipollini, Sean Kelly and Roger De Vlaeminck accounting for another 13 San Remo wins.

Then there’s the race itself. At 298 kilometers (actually 305.5 kilometers if you include the neutralized ride out of the city of Milan), it is by far the longest classic. That ultra distance has a huge influence on the manner in which Milan-San Remo is raced in the closing stages. When athletes have been in the saddle for some seven hours, the final two climbs, the Cipressa (22 kilometers from the finish) and the Poggio (just 6.2 kilometers before the line), can feel like alpine passes rather than lowly hills. That’s because these are big-ring climbs where the leaders can reach uphill speeds of 45 kilometers per hour when they jump clear near the Poggio summit—where Nibali was caught after a sudden attack last year and where he hopes to be far enough ahead this Saturday to claim his first monument.

Over the decades, the characteristics of the race have changed dramatically along with the state of the roads, the efficiency of the bikes and the fitness of the participants. When the legendary French hard man Eugène Christophe won Milan-San Remo in 1910, endurance rather than speed was the fundamental quality, and he was the winner over just two other finishers from 71 starters. Racing on dirt roads that soon turned to mud, Christophe took 18 hours to complete the 290 kilometers, riding through biting cold and snow showers, sometimes walking to keep his blood circulating. At one point, he stopped at an inn for half an hour, had a complete change of clothes, and only continued after warming up with a generous mug of hot toddy. The cold temperatures and enormous effort did so much damage to his body that Christophe was recovering for a month in the hospital, and he didn’t return to full health for two years.

The most vaunted of Coppi’s three San Remo victories was the first, in 1946. The roads were still not surfaced, but that day was dry and the dust was the enemy rather than mud. Coppi made a seemingly stupid move by joining a nine-man break after only 20 kilometers, along with the Frenchman Lucien Teisseire. On the early slopes of the classic’s highest climb, the Turchino, Coppi and Teisseire left the others behind; and then, a kilometer from the summit, Coppi accelerated clear, even though there were still 140 kilometers left to race. A 100-meter gap at the top turned to eight minutes on the descent, after the Frenchman was blinded by clouds of dust thrown up by cars following Coppi. By San Remo, Coppi was 14 minutes ahead of runner-up Teisseire and more than 18 minutes ahead of the chase group that contained Coppi’s archrival, Bartali.

Merckx earned his record haul of seven San Remo wins in an 11-year period by nearly always making his crucial attack on the Poggio—sometimes on the descent rather than the uphill—and taking the win alone or in a final sprint against a handful of rivals. Successful solo breakaways have been rare in postwar years. One was the totally unexpected triumph by Italian team rider Michele Dancelli in 1970. There was the even more shocking success by French journeyman racer Marc Gomez in 1982. And the most popular solo victory was that of homeland hero Claudio Chiappucci, the last survivor of a four-man move that started in a rainstorm on the Turchino.

As well as La Classicissima, Milan-San Remo is often called La Primavera, the springtime, because its traditional March date heralds the new season. Every year, beside pollen from the mimosa blossom, there’s electricity in the air when the peloton swoops down from the Apennine peaks to the Mediterranean and heads along the spectacular Italian Riviera to San Remo, the City of Flowers.

The race has changed with the recent addition of Le Manie, a 1,000-foot climb of 4.7 kilometers, that the peloton tackles 94 kilometers from the finish. Last year, the speed of a relatively small group of leaders up this hill allowed them to stay clear of a main pack that had been delayed by a pileup on slick roads. That’s how Cavendish missed out and his then teammate Goss got his chance to win. Cavendish is now with Team Sky, Goss with GreenEdge, and both are among the elite list of potential winners, as are two other former winners, Cancellara of RadioShack-Nissan-Trek and Freire of Team Katusha.

But with rain in the forecast for the final three hours of this year’s Milan-San Remo, a solo winner might again be in the cards. If so, then the tifosi could well get their wish of success for Nibali, whose brilliant win earlier this week at Tirreno-Adriatico has given him the drive to join Coppi, Bartali and Girardengo on the illustrious palmarès of La Classicissima.

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