To be perfectly honest, I wasn't that excited to visit Pier 39 on my second day in San Francisco. I generally try to stay away from tourist traps, but the pier was much more enjoyable (i.e. less crowded) than I thought it would be! It really helped that I went on a weekday morning haha. I strolled along the pier, explored a few of the souvenir shops, ate a delicious (but overpriced) pasta lunch, and even saw a few sea lions! It's a good place to bring any first-time visitors to SF, but I'd strongly suggest going during non-peak hours.
+ Visitor tip: Use this coupon to get a free Pier 39 Fun Pack at the California Welcome Center. It comes with all sorts of coupons, including free 2-hour parking. Most of the restaurants on the pier will only give you one hour of free parking, so this is a great deal!