Dry Tortugas-- a good choice

I hate water and scare of any swimming pool deeper than 4 feet. But I never regretted visiting Dry Tortugas. It's one of the most beautiful places I've ever been. We spent three hours on the island, including two hours of snorkeling. If you don't like historical visits, you can actually go snorkeling directly. We were there in summer, and got sun burns on our back since we forgot to put on sun blocking cream. Don't know about water temperature in winter. If you can go snorkeling there, it's definitely a place you don't want to miss. Actually, compared to your visit to Dry Tortugas, glass boat would become a waste of money.