Live blogging the Boston Marathon

Every year, about 20,000 runners from nearly every corner of the world test their physical limits in the Boston marathon, America's first modern marathon course. This year the race is again reported to be one of the biggest - WBZTV reports that more than 25,000 people registered for the 2008 trek, a number second only to 1996's record 38,000 entrants on the race's 100th anniversary.

All day today, the media will offer vignettes of the some of the race's more notable runners: Seven-time Tour de France champion Lance Armstrong will compete, as will 2007 champs Robert Cheruiyot and Lidiya Grigoryeva. Many more students, professionals and retired people will test their own limits making it to the finish line. Some will race for charities supporting everything from Esplanade upkeep to cancer research, while other disabled participants, some of them in wheelchairs, will depart early from rural Hopkinton, Mass. to prove they belong here as much as anybody.

Yet to the average Bostonian, the story is as much about cheering bystanders and traffic snarls as it is about a friend competing in the race. Thousands of volunteers are turning out to maintain this local circus by providing first aid to runners, keeping crowds in check along the route's more crowded corridors and preventing the most daring spectators from swiping mile markers for personal souvenirs. Throughout the day, this blog will hear these people's stories and give irregular updates on the state of the race as it tears through Boston for runners' final few miles. Wi-fi willing, you will hear about it as it happens.