Cape Cod sisters Mackenzie Sisson (left), 24, and Rebecca, 23, are running the Boston Marathon for the second time. They're hoping that it's not too hot today.
Loading the buses on Marathon Day
Cape Cod sisters Mackenzie Sisson (left), 24, and Rebecca, 23, are running the Boston Marathon for the second time. They're hoping that it's not too hot today.
(Boston.com Staff Photo / Adrienne Lavidor-Berman)