Nantasket Beach is in Hull, MA on the South Shore, 45 mins south of Boston. Tends to be less crowded than The Wall (your other closest option if you live in the Boston area) but the breaks are a bit more unreliable. Nice sandy beach with few hazards, no 'localism' that I have encountered. Summer is pretty flat (long board is best) but Fall and Winter the waves are reliably decent. The water is about 2-3 degrees warmer than The Wall in NH too (expect low 60's in the summer, high 30's in the winter).
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