Marathon Route - Commonwealth Avenue @ Massachusetts

[NadCixelsyd]

Does the Marathon go under Mass Ave, or do they take the exit and
cross Mass Ave at grade. In other words, is Mass Ave open to
vehicular traffic during the Marathon?

[Jimmy]

Post by NadCixelsyd
Does the Marathon go under Mass Ave, or do they take the exit and
cross Mass Ave at grade.  In other words, is Mass Ave open to
vehicular traffic during the Marathon?

I had thought they used the underpass in recent years. But
http://www.boston.com/sports/marathon/course/streetclosings/ says Mass
Ave is closed from Beacon to Belvidere.

Jimmy