As wind whips over the vast fields and tall red barns nearby, Andrew Folpe prepares his aluminum-framed gravel race bike for an early-morning ride.
With 40 mile-per-hour gusts, his morning training ride will be a test of endurance, a fitting preparation for Saturday's 100-mile Almanzo road race, which will test more than 1,000 cyclists from around the country and Europe on the winding, backcountry roads just south of Rochester.
One of the nation's premier gravel road events, the race gets its name from Almanzo Wilder, the husband of "Little House of the Prairie" author Laura Ingalls Wilder. The couple lived for a brief period in Spring Valley, where this weekend's bike race is based.
"The gravel roads in Minnesota are much hillier than the regular roads," said Folpe, 46. "They haven't been graded. So they're more fun. The best parts of it are when it goes through the valleys and the bluffs."
On his recent morning ride, Folpe attacks the road with his friend and fellow cyclist Joachim Mertens. Both men work at Mayo Clinic. Folpe is a doctor and professor of laboratory medicine and pathology; Mertens, also a doctor, is a postdoctoral research fellow in gastroenterology.
Maneuvering a bike on gravel is hard work, both physically and mentally, even for the two veteran cyclists. There's a lot of bouncing. Roads are dusty and can be filled with potholes, or covered in tiny, crushed limestone rocks that pop from the ground and wedge themselves into riders' knees. If it's wet, roads get slippery and slimy like crunchy peanut butter.
Mertens, 36, said the ride requires constant mental focus.
"Gravel road is really the way to go if you want to avoid cars as good as you can," he said. "Its landscape is beautiful, and it's more challenging terrain. You have to be careful when you pull out your bottle and take a sip, because you don't want to do that in the wrong corner. At least I don't want to."
In its seventh year, the Almanzo will wind through some of southeastern Minnesota's most remote areas. But it's not really a competition. There is no entry fee, and the only rule is that riders finish in 12 hours. Riders can use whatever kind of bike they want. And instead of claiming a prize, the winner takes home a Mason jar full of gravel.
"It is a race, but in all honesty I couldn't tell you who's ever won," Folpe said. "The whole thing is very casual. It's a nice group of people. It's certainly a lot more low-key than road racing."
The Almanzo has grown each year, from 12 riders in 2007 to 1,300 this year.
Founder Chris Skogen, 35, who organizes the informal race from the attic of his home in Rochester, is a manager at Trader Joe's. He spends his nights and weekends personalizing race packets with hand-written notes, promoting the race on social media and collecting postcard registrations from fans around the country. Most participants are men, but women have started to ride in the last couple years.
"I know there's some people out there that think I'm crazy for allowing so many people in," Skogen said. "But if you are inviting people over to your home, how do you pick which ones you don't want to be there, if you really genuinely want to have this experience with all these people? It's hard to say no to somebody."
Skogen said the race has become a grassroots alternative to traditional events that emphasize podium ranking. Similar races have emerged in towns and cities across the country.
"Cycling is not at the forefront of people's minds like basketball or baseball," he said. "So for me it was important to try to do something a little bit different, and shift the focus from the top three to the entire field in the hopes that it would get more people interested."
If convincing people to enter a 100-mile gravel race wasn't enough, Skogen upped the stakes, challenging some riders to push their limits even further. This year, about 70 cyclists will ride a 162-mile route and another 30 will tackle a grueling 380-mile loop -- all on gravel.