The French governing body of professional cycling, Union Cycliste Internationale, has rated the 2012 USA Pro Cycling Challenge the most difficult classification for any stage road race: hors categorie, or "beyond categorization." This intimidating route will take riders through nine alpine passes, three of them in excess of 12,000 feet, elevations unheard of elsewhere in cycling. The lack of oxygen, combined with steep climbs, will seriously test riders' conditioning and talent.
Here's a glimpse at what the peloton will face each day.
DAY 1: Durango to Telluride
Distance: 125.6 miles
Riders begin the tour with the first of many long, grueling road stages. Following a sprint through Durango, they'll face a 30-mile climb to the 10,222-foot Lizard Head Pass summit — about 4,000 feet higher than where they began the day. The last 15 miles, however, promise a steep, thrilling descent into Telluride.
DAY 2: Montrose to Crested Butte
Distance: 99.2 miles
One of the shortest stages of the week, this one is almost entirely uphill. Making good times early will likely help racers later, especially with an ultra-steep, alpine climb for the final miles to the finish on Mount Crested Butte.
DAY 3: Gunnison to Aspen
Distance: 130.5 miles
The longest day of the week also boasts its highest point, the towering 12,126-foot Cottonwood Pass. Still not impressed? The 14-mile climb leading up to it is all dirt track. After a descent, riders will summit yet another 12,000-foot pass, Independence.
DAY 4: Aspen to Beaver Creek
Distance: 97.2 miles
After tackling it at the end of Day 3, cyclists head back up Independence Pass to start Day 4. From there, the trend of the track is downhill, but the route has a bit more up its sleeve; the final 2½-mile climb rises a staggering 1,000 vertical feet to the finish line, demanding riders conserve their energy throughout the day, despite the temptation to bomb the downhill stretches.
DAY 5: Breckenridge to Colorado Springs
Distance: 117.9 miles
Another mostly downhill stage, this one too begins with a daunting climb, followed by downhill cruises, a sprint-line in Woodland Park, a tour of Garden of the Gods, and a finish of circuits around downtown Colorado Springs. Riders should hit their fastest speeds of the week coming into Woodland Park.
DAY 6: Golden to Boulder
Distance: 103.3 miles
For American racers, this is "home-field advantage." Road cyclists frequently train on these hills, thanks to their similarity in profile and climate to the European Alps. The day begins with Tour de France-like rises and descents, finishing with a hard climb into Boulder that could decide the race going into its final day.
DAY 7: Denver
Distance: 9.5 miles
Up until now, racers have been competing in teams, using each other to draft and block rivals while playing on each others' strengths in climbing or sprinting for maximal speed. Today, that all changes. This 10-mile time trial will have each racer leaving the starting line to race the flat, urban track all by himself. Climbing experts will hope to enter the race with a large enough lead to hold off the sprinters, and time-trial specialists will hope their hard work all week long will put them in contention with a fast time today.
Five to watch
One hundred and twenty six riders from 24 countries will hit top speeds and altitudes throughout the USA Pro Cycling Challenge. These Americans will be among the most talked-about:
1. Levi Leipheimer: Leipheimer, with Team Omega Pharma-Quickstep, is coming off an exciting final-stage win at last week's Tour of Utah. He's also the Challenge's defending champ.
2. Tom Danielson: Boulder resident Danielson, with Team Garmin-Sharp-Barracuda, separated a shoulder in a bad 2012 Tour de France crash. But he rode well in the Tour of Utah, finishing 11th, so he seems ready to race for yellow here.
3. Timmy Duggan: Not only did Duggan represent the United States in the London Olympics, but the Team Liquigas-Cannondale member won the 2012 USA Cycling Pro Road National Championships. Definitely one to follow as he takes to the streets of his home state.
4. Tejay van Garderen: Van Garderen, 23, has earned four young-rider jerseys in four different top races since the start of 2011, including the inaugural USA Pro Cycling Challenge, so it's easy to see why in July Sports Illustrated labeled the BMC Racing Team member "the future of cycling."
5. Tyler Farrar: Farrar had some bloody and challenging days in this year's Tour de France, but Danielson's teammate is a strong sprinter. So Stage 5, in particular, could be Farrar's to win.
— Kirsten Akens