Photo: Olivia Nadel

For its milestone 10th year, the Boston Book Festival once again takes over Copley Square, offering the chance to see and hear a roster of more than 200 authors at various Back Bay venues on October 13 from 10 a.m.–6 p.m. for free. A ticketed kick-off event featuring a keynote address from renowned writer Michael Pollan (The Omnivore’s Dilemma) takes place at the Old South Sanctuary on October 12 at 7:30 p.m.—no doubt getting the festivities off to a rousing, eye-opening start—while historian Doris Kearns Goodwin and former Secretary of State John Kerry make appearances at another ticketed event Saturday afternoon at the same location.