You'll love Mackinac Island; it's truly a magical place! If you're able, be sure to rent a bike and travel all the way around the island. It's an easy trek, and you really get to see things including nice spots to rest and wiggle your toes in the clear blue waters of Lake Michigan. Since you're staying at the Grand Hotel (lucky you!) be sure to partake of an Afternoon Tea. And also be sure to walk to the left of the hotel up a short stretch of road -- the homes there are well worth seeing. I don't have to tell you to relax along the veranda in the rockers and take in the view. Enjoy your wonderful trip!