Like anywhere, you’ll feel like you're in the know when you manage to avoid the crowds. In Charleston, plan your downtown sightseeing for the morning, before the heat settles in, and scoot to Sullivan’s Island or Folly Beach after lunch to catch the afternoon breeze. Spoleto and the springtime festivals are an excellent time to visit the Holy City, but book accommodations well in advance, or stay at one of the neighboring beaches and commute 20 minutes into town for day trips and dinner. Columbia slows down and swelters in the mid-summer heat, and is best visited during the spring and fall when USC is in session and the city hums with activity (reserve a room early if you’re there on the same weekend as a USC football game). Greenville is pleasant all year, but comes alive in the fall when the surrounding mountains glow yellow and orange with the falling leaves.