Bergen is pleasant year-round, but summer and early autumn are the peak season. The beaches at Bergen aan Zee fill up in July and August, so accommodation books out fast — reserve ahead if you're coming then.
August is the month for classical music: the International Holland Music Sessions brings young professional musicians to Bergen for three weeks of masterclasses and daily concerts, many held in the Ruïnekerk. Catch at least one evening there if you can.
Early September brings Jazz & Sail — three days of jazz in the village and on the beach at Bergen aan Zee, combined with catamaran racing on the water. It's lively and free to attend. More at jazzandsailbergen.com.
October is for art lovers: the Kunsttiendaagse (Ten Days of Art) has around a hundred local artists opening their studios to visitors. It's a rare chance to see how the work gets made and to talk to the people behind it.