Keep your fitness going the following weekend too! On September 21, Boston.com kicks off its sixth annual Blue Cross Blue Shield of Massachusetts Island Run on Spectacle Island. Participants can choose between two separate races: a 5-miler and a 5K race. Both races share the same start and finish lines, with the 5M starting ~25 minutes before the 5K. Afterwards, enjoy a celebratory lunch, drinks (21+) and an award ceremony on the Provincetown-II while cruising through Boston Harbor. This event is family-friendly, but the course includes trails which are not stroller-friendly. Friends of the Boston Social Fitness Festival can receive $15 off your race entry fee by using code RUNNING.