Cinque Terre National Park in September

April through June and September through October offer the sweet spot - mild weather, blooming flowers or fall colors, and manageable crowds. May is particularly lovely when wildflowers carpet the hillsides and temperatures hover around 20°C. September brings the grape harvest and perfect hiking weather. July and August are beautiful but brutal - expect sweltering heat, packed trails, and long waits for trains. The villages practically shut down in winter, with many restaurants closed and rough seas canceling boat service. Spring can be unpredictable with occasional rain, but you'll have the trails largely to yourself. For photography, the golden hour light in late afternoon makes the colorful houses absolutely glow, regardless of season.