I agree that for a 5 day visit, if you want to relax, choose only one island and take time to explore. I have been to many islands, Naxos (my FT name) is my favorite, but may not be right for the first timer. Sanotrini has dramatic scenery and archeological sites and manytourists. If the meltemi is blowing, the ferry ride will not be pleasant. Consider flying so you do not have to spnd 2 precious vacation days on ferry boats. Paros and Naxos are lovely islands in the Cyclades- larger islands with many beautiful long beaches and tavernas and lots of variety. They are closer to Athens than Santorini. Naoussa, a fishing town on Paros is a delightful place to stay- if used as a home base you can travel by caique (small boat) to other beach areas or rent a moped or take a bus to ther parts of the island. You could even take the ferry to NAxos- several a day for a 1 hour trip. Naxos is larger still, with a lovely Old Town area. A basic, but clean hotel, Anixis is located in the old town, pedestrians only- the quintessential Greek postcard perfect picture white wahshed flower bedecked setting. From the port area you can take busses or boats to the beaches and return in the evening for dinner and promenading along the quayside (paralia) as the Greeks and the tourists alike do each evening. The island has many beaches, each with its own character- some windy for windsurfers , others for lazing on the beach- lots of beach tavernas. Naxos is a large island and may not strike one as the most picturesque from the harbor, but it has lots of variety and extraordinary scenery- a tour of the island is essentail to capture the beauty of this place. Amorgos and Folegandros are smaller cycladic islands, but you have a short time and ferry service to the smaller isladns is less frequent and if the Meltemi is blowing, ferry service can be temporaritly suspended. I would recommend a place to which you can fly. I have spent lots of time in Greece over the past 30 years- so if I can help let me know.
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