And you always thought that Bloomsday was the world's largest individually timed road race (after all, so goes the promotional material). Actually, it's the world's largest individually estimated road race.
You didn't think they had a TAG Heuer chronograph devoted to you in particular, lasering in as you strain to break the vaunted two-and-a-half-hour barrier. Did you?
"Starting at 28 minutes [into the race], a time frame marker is moved up each chute every 30 seconds. These are just a larger version of the tearaway tag that you take off your pinned number as you cross the finish line. So as you come in, you'll fall between two of these markers, of course."
So says Max Bischoff, who should know; he's been a Bloomsday volunteer for 25 years and for the last three has overseen the 250 folks who are dedicated solely to finish line record-keeping.
"If you come in under an hour," explains Bischoff, "there will only be three or four chutes open. Twelve is the maximum number of chutes. The computer then arbitrarily establishes [a runner's] position relative to the other 11 chutes. Theoretically, it should be within 15 seconds of your actual clock time."
Before you age-group competitors start whining about unfairness, consider the logistics for a moment. When the finisher-flood peaks in a Bloomsday race, 20 people cross the line every second.
Try recording that with pen and paper and some poor schlubb next to you shouting out elapsed times and numbers. Even with staggered starts, every minute there are still as many as 900 runners, joggers, walkers, strollers and stragglers crossing the 12-kilometer line.
After the race tags are collected, they "are taken to the south end [of the finish area] in numbered sequence, and then taken by bicycle messenger to our new tabulation center over on West Broadway."
And that, my sweaty friend, is how your time (give or take) shows up in some obscure local newspaper on Tuesday mornings.
Sound easy? Consider this. The race that is logistically most similar to Bloomsday is the Peachtree Road Race in Atlanta. Except it's only a 10K. And they cap it at just 50,000 runners. And times? Well, they've got the first 2,000 finishers covered. "After that," says Bischoff, "it's just cross the finish line, stroll into the park and pick up your T-shirt."
As for your individual time in Atlanta? Well, you can estimate what you really did, subtract 10 minutes, then try to impress everybody with your supposed time. Or you could actually run Bloomsday and find out for sure.