Boston is worth visiting any time of year, but autumn is the most beautiful season. New England is famous for its fall foliage -- golds, reds, and oranges flaming from the trees from late September through October. Temperatures average between 50 and 70 degrees and the summer humidity disappears.
Summer brings outdoor concerts at the Hatch Shell and the Fourth of July fireworks on the Esplanade. Winter is cold and snowy but the city has a cozy charm, with skating on the Frog Pond and fewer tourists.
The Head of the Charles Regatta in mid-October is a major event, with over 7,500 rowers competing on the Charles River. The Boston Marathon on the third Monday of April effectively shuts down the city for the day. King Richard's Faire, a Renaissance festival in nearby Carver, runs weekends from September through October.