Kayaking along Pictured Rocks National Lakeshore, Upper Peninsula, Michigan. I did this for vacation last year. It's an eight hour day trip along the Pictured Rocks. Breath taking and well worth the money you spend on the experience!
Whitehaven Beach, Queensland, Australia is a 7 km stretch along Whitsunday Island. The island is accessible by boat from the mainland tourist ports of Airlie Beach and Shute Harbour, as well as Hamilton Island.