If you plan to watch races on TV or read about racing in the past, it is helpful to have some idea of the constellation of great racers and the events that have made their reputations.

There are many bike races, but the top of the heap are the Grand Tours, races that unfold over three weeks. There are only three in the world, taking place annually in France, Italy, and Spain. The Grand Tours include 21 stages with two rest days.

Tour de France: The Tour, as it is known, is the world’s largest annual sporting event in terms of TV and live viewership and the most prestigious of all bike races. Each day a new race—called a stage—is run, often between two cities.

The race begins with a short time trial, called the prologue. The riders’ varying times give each competitor an overall placing and also indicates who some of the strongest contenders may be. In some years there is a team time trial, in which each team’s nine riders ride a time trial working together in a pace line.

Stages take several forms. Most are mass-start events and often cover more than a hundred miles in distance. Some stages climb the high mountains of the Alps and Pyrenees. Climbs are classified from 4 (the lowest) to 1 (very high) and even those called hors categorie (H.C.—beyond category), reserved for the very highest mountains. Each year several stages will finish atop mountains.

The race is judged on overall accumulated time. The rider with the lowest accumulated time is the race’s General Classification (GC) leader and wears a yellow jersey. The race awards jerseys for three other classifications. The points competition gives a green jersey to the best sprinter. The mountains competition (often called the King of the Mountains) gives a red-and-white polka dot jersey to the best climber. The young rider competition awards a white jersey to the best overall rider under the age of 25.

Because of the incredible prestige a win in the Tour de France carries, riders from all over the world make it the focus of their season. Not a single French rider has won the Tour de France since 1985.

The Tour de France was first run in 1903 and has only been suspended 11 times, during World Wars I and II. Initially the race had few stages (the 1903 edition had just six stages), but the stages ranged between 167 and 263 miles in length—long by today’s standards (the race totaled 1,509 miles). In 2008, the Tour had 21 stages; the mass-start stages ranged between 89 and 144 miles for a total of 2,212 miles.

Tour of Italy: The Giro d’Italia is the second oldest and second most-popular of the Grand Tours. The Giro is held in late May and June.

The Tour of Italy has never carried the worldwide adulation that the Tour de France enjoys. As a result, it remains a bigger priority to Italian riders than non-Italian riders, which explains why Italians, including an 11-year streak from 1997 to 2007, have won the majority of Giro.

The race is judged on overall accumulated time. The rider with the lowest accumulated time is the race’s General Classification (GC) leader and wears a pink jersey. The race awards jerseys for three other classifications. The points competition gives a mauve jersey to the best sprinter. The mountains competition (often called the King of the Mountains) gives a green jersey to the best climber. The young rider competition awards a white jersey to the best overall rider under the age of 25.

The Giro was first run in 1909 and has been suspended only nine times, during World 

Wars I and II.

Tour of Spain: The Vuelta a Espana is the third oldest and third most-popular of the Grand Tours. Originally held in April, the Vuelta was moved to September in 1995.

The Vuelta a Espana has never carried the worldwide adulation that the Tour de France enjoys. As a result, it remains a bigger priority to Spanish riders than non-Spanish riders, which explains why nine of the last 20 Vuelta have been won by Spaniards.

The race is judged on overall accumulated time. The rider with the lowest accumulated time is the race’s General Classification (GC) leader and wears a red jersey. The race awards jerseys for two other classifications. The points competition gives a mauve jersey to the best sprinter. 

It was first held in 1935, though intermittently; it has been held annually since 1955.

Five races—Milan-San Remo, the Tour of Flanders, Paris-Roubaix, Liege-Bastogne-Liege, and the Tour of Lombardy—carry the distinction of being called the Monuments. They are so named because they began prior to World War I; the youngest of the events, the Tour of Flanders, was first run in 1913. The roads they travel were used during the World Wars and now the courses are lined with memorials to the war dead.

Milan-San Remo: At 298 km (185 miles), Milan-San Remo is the longest of the five Monuments. Traditionally run the third week of March, Milan-San Remo signals the shift into high gear for the Spring Classics. The race is held in Italy and its course runs from the city of Milan to the small town of San Remo on the Ligurian coast near the French border. Conditions are generally cold at the start but with the run to the coast, the finish is much warmer. The course features several significant climbs and the final two, the Cipressa and Poggio, are effective at thinning the pack so that only the strongest sprint for the finish. Italians have won the race in 50 of the 99 editions. Belgian Eddy Merckx holds the record for the most wins with seven.

Tour of Flanders: The Ronde van Vlaanderen is the first of the Northern Classics. It is generally run the first Sunday in April, one week before Paris-Roubaix. It covers a 262 km (163-mile) course from Brugges in the north to Ninove outside of Brussels. It is famous for its 17 hills, which range in length from 375 meters (410 yards) to 2.2 km (1.4 miles). The climbs are called “muur” (wall) because many are steep at some point; 11 of the hills have sections with gradients of 11 percent or more and eight have sections made up of cobblestone. If the roads are damp, riders are frequently forced to dismount their bikes on the steepest sections of hills and walk up. It’s a bit like trying to climb a mountain in your dancing shoes. Many Belgian riders have said that winning Flanders is more important to a Belgian than wearing the yellow jersey of the Tour de France. Belgians have won the race 65 of the 92 times it has been run. Achiel Buysse, Fiorenzo Magni, Eric Leman, and Johan Museeuw are tied for the record of most wins, with three apiece; all are Belgians except for Magni, an Italian.

Paris-Roubaix: Considered the “Queen of the Classics,” Paris-Roubaix is the only Monument run in France. Best known as the “Hell of the North” for the sections of cobblestone roads it traverses in Northern France, it is held the second Sunday in April.

Over its 260 km (162-mile) course, Paris-Roubaix submits riders to 28 sections of pavé (French for cobblestone). The sections of pavé range in length; some are as short as 200 meters (218 yards), while the longest are 3.7 km (2.3 miles). The sections are rated in difficulty from one star (easy) to five stars (reserved for the most difficult sections). These are the same cobblestone roads used in World War I. The most famous (and difficult) sections—the Arenberg Forest, Mons-en-Pevele, and Carrefour de l’Arbre—are traditionally the site of attacks that can tear the race apart. The cobblestones jar the body terribly, can be slippery, and are the source of untold numbers of punctures. Riders will run exceptionally low tire pressure (sometimes as low as 50 psi) in an effort to cushion them from the rough surface and reduce the likelihood of a puncture. Most don’t finish the race due to one or another of the many setbacks a rider can encounter. As a result, riders speak of the luck required to win at the velodrome in Roubaix. Crashes are frequent and often spectacular; it’s kind of a full-contact roulette.

The day’s weather can make a big difference in the race; if there’s rain, racers can be forced to ride through mud, while on dry days dust can affect racers’ breathing and vision. Imagine trying to skateboard through a quarry and you’ll have the idea. Though the race is French, it is a particular favorite of the Belgians, who have won it 52 times in 106 runs. Roger De Vlaeminck holds the record for the most wins: four.

Liege-Bastogne-Liege: As the oldest of all the Classics—first held in 1892—Liege-Bastogne-Liege is called “La Doyenne” (a sign of respect, something like Grand Dame). It is one of two Classics held in the Ardennes region of Belgium (the other is Fleche-Wallonne) and is known for an exceptionally hilly course with 12 notable climbs. Liege-Bastogne-Liege is held the last Sunday in April over a 261 km (162-mile) course. The course only takes in two of the 12 climbs in the 105 km run from Liege to Bastogne on the trip south, but after leaving Bastogne, the riders are taken on a circuitous route over 10 of the 12 climbs. And while the race is called Liege-Bastogne-Liege, the race’s finish is in the town of Ans, which is a bit like having a race called Denver-Colorado Springs-Denver finish in Boulder. Belgians haven’t fared so well in their race since Eddy Merckx’s last of five wins (the record) in 1975. Since then, only four Belgians have given a salute in Ans.

Tour of Lombardy: The “Race of the Falling Leaves” is the only one of the Monuments held in the fall. The running of the Giro di Lombardia signals the end of the season for most top riders. Generally held the second or third week of October, the Tour of Lombardy was originally called Milan-Milan, the course has changed many times; today the start takes place in Varese and the 242 km (150-mile) race finishes in Como on Lake Bellagio. The race contains a number of significant climbs, with six of them notable for their length. The race’s most difficult challenge is the climb up to the historic chapel of the Madonna del Ghisallo, which holds bikes and memorabilia of many great former riders. The 8.6 km (5.3-mile) climb contains a maximum grade of 14 percent. The race is an overwhelming favorite of Italian racers, who have won 67 of 102 races. Fausto Coppi holds the record for the most wins: five.

Unlike some sports where the World Championship is awarded based on points accumulated over the course of the season in important races, in cycling the World Championship is awarded based on a single race, which moves location each year. First held in 1927, the race was held in August after the Tour de France, but was pushed back to September following the 1995 move of the Vuelta a Espana to August. Most of the prominent cycling countries have hosted the World Championships at one point. The United States hosted the World Championships in Colorado Springs in 1986. Because the course changes each year, its challenges and length do as well; in some years the race is flat and ends in a sprint, while other years feature hills that can result in a solo breakaway. The World Championship road race is the one time each year riders set aside their team affiliations and race under the flag of their country; this temporary change of affiliation isn’t without its problems, but riders often come together to form a remarkable alliance. A World Championship is held in both the road race and time trial, and the winner wears a rainbow jersey for the next year. Four riders have each won the World Championship road race three times: Alfredo Binda, Rik Van Steenbergen, Eddy Merckx, and Oscar Freire.

The United States has had a number of high-quality races that have attracted top-quality international fields. The first great U.S. stage race was the Coors Classic (which started as the Red Zinger in the mid-1980s). The Tour DuPont, the Tour de Georgia, and now the Amgen Tour of California followed it.

With eight days of racing, the Tour of California is one of the longest stage races run on American soil, and other than the 1986 World Championships in Colorado Springs and 1996 Olympic Games in Atlanta, it draws the strongest international field of racers to be assembled in the States. The race has been hailed for spectator-friendly and challenging courses, great organization, and fantastic racing, as well as occasionally stellar weather.

After many years in Philadelphia, the National Championship road race is now held in Greenville, South Carolina, over a demanding course in hot and humid conditions.

Races in America tend to have unfortunately short life spans because they rely on corporate sponsors for their existence. As soon as their marketing priorities change, the races often fold due to an inability to replace the title sponsor willing to put up the bulk of the necessary funding. The pullout of a sponsoring corporation has made races disappear faster than a Star Trek crew member from the transporter room.