For Naxos:
HIKING - the best-known online guide to hikes - http://www.cycladen.be/NaxosEng.htm - by a Belgian who's spent a lifetime trying & describing hikes & walks in all the Cycladic islands, calls Naxos "a paradise for hikers." There's 1 hike in Santorini that everyone takes, the Belgian hikemaster lists 37 in Naxos that he recommends.
MUST-SEES - I always dislike this term, because it calls up an image of a to-do list which one can check off, and then say "There! That's done!" Naxos is a treasure-house of Must-sees ... ancient ruins on hilltops, statues lying in orchards, Mountains with whole sides open to show that they are MARBLE ... mountain villages still living very traditionally ... a port town with a maze of winding lanes to get lost in ... discoveries everwhere (the Cathedral decided to repave its courtyard, and found a 4,500-year-old Mycenaean burial ground, with the ritual dishes still in place!) ... a string of golden sand beaches about 15 miles long, served by a great bus route. What MUST one see? Well, one May, we drove a couple of miles inland and found a man shearing his sheep. We decided we must stop and watch for half-and hour. In early September, the villages around the vineyards have wine festivals -- you may decide you want to drive up there and share the sipping. Sunsets? Every night you can sit on the beach, or at a portside taverna and watch a sunset, with NO maddening crowds ... or go out to the Causeway, and photo the setting sun through the famous arch. There is no Famous Sights checklist ... make your own!
RESTAURANTS - Greeks don't call them that; they are called tavernas (meaning they have authentic food, checked tablecloths, informal welcome, and VERY low prices). A few to try in Naxos Town: To Kastro (High above on a terrace overlooking port), several port-side favorites are "The Good Heart" and "Smyrna" and "Popi's" ... a new place in town, Nostrimon Hellas, modern twist on authentic dishes ... Maros, off the town square, VERY local, you order what they've made for that night, as long as it lasts. All the restaurants feature some seafood; be aware that fish is scarce, and costly all over GReece (aside from smaller fish like sardines, and 'arides, and seafood like calamari & grilled octopus). In most of authentic places, your tastiest options are whatever is "fourno" (oven-baked) ... cooked low & slow, full of flavour. Baked chicken & lamb, veal stews (Stifado), stuffed vegetables. Yummmm.
WEATHER -- the old joke is that on the 1st Day of Creation, God went around passing out weather, but He overlooked Greece, and looked in the Weather-bag & He had run out. So He had to give Greece the weather He had been saving for Paradise. Diuring the day in Early September it can get up to 85°F, but by sundown it will be 70. and you'll want a light sweater over your shoulders, and by the time u get back to your room it will be 63 - 67. Perfect sleeping weather. PS: if you like your windows open, a tip to avoid Mosquitos (there are no screens in Greece). Close windows AND shutters before you go out to dinner. When coming back, leave them closed until u are in bed. Turn out lights THEN open windows ...
CAR RENTAL -- There are half-a-dozen good places, several on the town seafront, and 3 on the Town Square (circle). Lots of models available in Sept. TIP: if you want to make an early start, say 8:30 or 9 for driving around the island, it's handy to rent the car the night before ... then u will have it bright & early. Agencies are sluggish in the AM, sometimes if u go to their office at 9, you don't get a car for 45 minutes or so. (Greek internal clocks differ from super-hyper US ones).