You can water-ski in the protected waters of Hamilton Harbour, Great Sound, Castle Harbour, Mangrove Bay, Spanish Point, Ferry Reach, Ely's Harbour, Riddells Bay, and Harrington Sound. May through September, when the waters are usually calm, is the best time for water-skiing. Bermuda law requires that a licensed skipper take water-skiers out. Only a few boat operators handle this sport, and charges fluctuate with fuel costs. Rates include the boat, skis, safety belts, and usually an instructor. Hotels and guesthouses can assist with arrangements.