I made my annual trek to downtown Somerville for the bike races. Not really a trek but less than a 10 minute car ride!
There are about 5 or 6 races for different classes of riders. All are very entertaining and the riders put in many weeks are hard work, some even a lifetime's worth.
Here is a video I took as the riders in this race approached the home stretch in one of their many laps around the course.
I only saw one accident during the day and it did not appear that there were any significant injuries.