The ‘marathon’ before the Boston Marathon

Hours before runners line up to begin the Boston Marathon on Monday, a different group will traverse the 26-mile route overnight on Sunday.

It’s time for the “Midnight Marathon Bike Ride.”

The annual tradition, which was started by Boston University student Greg Hum in 2009, invites hundreds of cyclists to pedal from Boston’s western suburbs into the city, just hours before runners line up in Hopkinton. It ends with a pancake breakfast.

Despite the name, the “marathon” is actually just a group bike ride, not a race, organizers say.

The ride begins in Southborough, north of the Marathon starting line in Hopkinton. Cyclists can choose between two different routes: Route A, which will take them 30.6 miles, or Route B, which will take them 27.3 miles. Route A joins the Boston Marathon route in Hopkinton and follows it into Boston. Route B joins the route at a point 4 miles farther along.

Cyclists, who are encouraged to take off at midnight, can arrange their own transportation to the starting line or they can take the 10:40 p.m. commuter rail from South Station Sunday night. People who take the train, where bikes aren’t allowed, can pay a fee to have their bikes put on a truck and taken to the starting line.

The Midnight Marathon is unofficial. This means that there’s “no official ride registration, ride leaders, road support, nor any official start or finish time, and most importantly, that you and your friends are responsible for your own safety,” according to the organizers’ website.

According to a Facebook event page, more than 800 people plan on riding Sunday night.

As for the breakfast? It’s going to be held at the Boston Common Coffee Co. Those attending will receive a plate with three pancakes, two bacon strips, and a choice of coffee, tea, or water.

Not a bad way to end a late-night bike ride.