A simple concept - bicycle the backroads of Fillmore County free of charge - has turned into a powerful movement as 1,500 bicyclists have signed up to participate in the bicycle races this weekend that are part of Wilderfest in Spring Valley.

Almanzo 100 founder Chris Skogen brought his bicycle race to Spring Valley in 2010. Since then it has grown each year in number of participants and events so that the activities now fill a weekend.

While his races are now drawing thousands of visitors to the area and have gained recognition throughout the United States and even abroad, Skogen still emphasizes that it is a simple concept.

"The biggest impact from these events is most likely found in the inspiration it sparks," said Skogen. "Whether on a bike or off, Almanzo exists to motivate people to get out and do more."

The races, now three for bicyclists and three for runners, are unique in that they are entirely free to participants and they are self-supported events on gravel roads.

The newest race, the Alexander, begins at 5 a.m. on Friday. A total of 35 bicyclists will journey nearly 400 miles through three states in this event that debuts in 2013.

Saturday, the Almanzo 100, the race that started it all and the most popular event with more than 1,300 participants signed up, begins at 9 a.m. The Royal 162, a 162-mile race that dips down into Iowa, also begins at 9 a.m. A total of 65 people have signed up for this race.

Sunday, the Wilder Foot Races, an event started last year, takes place with 40 entrants registered. The Abel, a 62-mile race named after Almanzo Wilder's great-grandfather, begins at 5 a.m. The Perley, which is about 22 miles, and the James, which is about 32 miles, begin at 8 a.m.

The biggest change this year is that all events will be based downtown with the community center as the headquarters. Skogen welcomes the change because it will provide a more central location for both bicyclists and local residents.

Broadway Avenue downtown will be blocked off early Saturday morning. The starting line for the Almanzo 100 is tentatively set for the intersection with Jefferson Street, but may be moved north to the post office or farther to fit in all the bicycles.

They will then head north, get onto Highways 16 & 63, which will be blocked off for about 15 minutes, then go up Warren Avenue to Tracy Road and out past the school onto gravel roads.

The community also has events in conjunction with the races. The Spring Valley Kiwanis Club has a spaghetti feed Friday from 5 to 8 p.m. at the community center. This is also when bicyclists may register.

Saturday are the annual city-wide rummage sales. Also, the Spring Valley Historical Society will open the museum Saturday and Sunday. A new item this year is a beer garden on Broadway in front of Valley Lanes from Main to Park streets, which will be blocked off all day.

Sunday, the Spring Valley Ambulance Service will be holding a fundraiser breakfast from 8 a.m. to 1 p.m. at the ambulance garage.

There are also several other events in Spring Valley, including a cardboard box city "homeless" project of the youth at Our Savior's Lutheran Church Friday evening and the 75th anniversary of First English Lutheran Church Sunday with a program at 1 p.m. Also, Kingsland will be represented at the school bus races at Deer Creek Speedway Saturday night. Local restaurants are also having specials.

Spectators are encouraged to view the races in Spring Valley. A few good spots suggested by Kathy Simpson, Deb Zimmer and Julie Mlinar of the tourism committee are on Broadway Avenue near where the bicyclists ride from Grant to Warren, or Section Avenue near the high school.

Although downtown will be accessible for the foot races, it will be too congested for the bicycling events on Saturday, they warned, so spectators are encouraged not to add to the congestion.

Also, while the race is underway, the race organizers would prefer the spectators remain in town because motorized traffic could pose a danger to participants.

"Ultimately, we would rather have fewer cars out on the gravel roads because that is one of the main reasons we are running there...fewer vehicles," said Dustin Harford, who organizes the foot races.

The races have gained a quality reputation with media outlets across the country and even in the United Kingdom featuring the events. A Minneapolis creative film agency made a short film of the race last year and it debuted at the Parkway Theater in Minneapolis in August.

Challenge Handmade Tubulars has made a bicycle tire called the Almanzo that is now for sale and other companies are tying into the events in Spring Valley.

Although the events have earned a reputation, Skogen remains true to his vision of keeping them free, which has been a challenge with the explosive growth.

The attraction is the challenge in not only the distance, but also the hills, gravel and riding or running with no support.

"We strive to break down the racing experience to the purest form possible in order to give runners a true sense of accomplishment upon finishing," said Harford "Out on the gravel roads you only have yourself to depend on, and this requires not only physical strength but also mental strength."