Boston Half presented by Dana-Farber Cancer Institute and the Jimmy Fund

Run by the Boston Athletic Association, this high-demand city half combines a serious elite field with a large mass race. General entry can fill quickly, with charity places often providing another route after open registration closes.

The course starts and finishes in Franklin Park and follows the Emerald Necklace along the Riverway, Jamaicaway, and Arborway, passing Jamaica Pond, Willow Pond, and Olmsted Park. Repeated rollers, especially late, reward controlled effort more than aggressive early pacing.

November can bring crisp, fast conditions, but cold rain and wind are credible risks around the park system. Dress for the pre-start wait, then avoid overdressing once the rolling course begins.