In 2017, as has been well documented on this page and elsewhere, the Birkie will split off the Korteloppet and run it on Friday, leaving Saturday alone for the Big Race. It’s a question of congestion: the Birkie has grown from 4,500 to 7,000 participants in the past 10 years. The start has been congested, but the real rate limiting factor is the finish; there are only so many people you can process through a town like Hayward, Wisconsin. Which got me to thinking: are there any other large, long-distance races which have such a high ratio of participants to local population? And, no, not just ski races, but races of any kind at least marathon distance.

I found a list of the 50 biggest marathons in 2015, with about 2000 or more participants. The Birkie, if ranked among these marathons, would rank the 11th biggest race in the country. But the other marathons are in big cities. 50,000 people run New York, but that’s just 1/165th the population of the city. Even races in smaller cities (like Grandma’s in Duluth) account for less than 1/10th of the local population. (There’s a marathon in DisneyWorld which has a very small official population, but the park itself hosts 50,000 visitors per day, and is basically in Orlando, so it doesn’t have crowding issues. Also, why in God’s name would you want to run a marathon at 5:30 a.m. in Florida? No, please, someone explain this to me.)

Anyway: Hayward? There are three finishers for every resident of the town. It would be as if 24 million people ran New York, or 250,000 ran Grandma’s. The only other race close is the Bataan Memorial Death March race in New Mexico, but even it has only two finishers for every resident of the town of White Sands (and while an official marathon, many finishers spend eight or more hours on the course, so it’s a bit more spread out). Otherwise, Big Sur has about a 1:1 ratio, and every other marathon is at least 7:1 or more. So by this measure, the Birkie is, relative to the size of the largest town on the course, the biggest race in the country.*

* that is, relative to the size of the town it finishes in.