Sifnos is a small island, but it has something for everyone! Here is a sample of activities; thank you to everyone who sent us ideas. Keep sending more!
HIKING There are over 100km of trails on Sifnos, so get out there and take a hike! A recent locally-funded project produced maps, newly-marked trails, and a great website and mobile app. Plan your ramble here: Sifnostrails.com
ARCHAEOLOGY Ancient sites, including mines, cities, temples, a tomb, and "The Sanctuary of the Nymphs," can be found throughout Sifnos. For a rundown of the most important sites, visit this webpage. During the 6th century BC, a network of 77 beacon towers dotted the island. They were used as lookout towers, lit for communication, and peasants sought refuge in them during pirate attacks. One of the best preserved, the White Tower, is located just northeast of Platis Yialos, on the road to Appolonia. You can see it on a map here: The White Tower
MUSEUMS Explore any of 5 museums on Sifnos, focusing on local folklore, archaeology, pottery, and ecclesiastic art. Use the drop-down Museums menu on this website to get information on each one. Make sure to scroll down for English: http://www.kastrosifnos.com/
COOKING LESSONS Immerse yourself in local agriculture and food with an intimate, private cooking lesson at a small farm. More information here: Cooking lessons on Narlis Farm. Cooking lessons are also available in a traditional home, available through Sifnos Alternatives.
SEA SPORTS Rent a paddle boat, canoe, or stand up paddle board at BlooMarine.
VISIT KASTRO The village of Kastro is as picturesque as it gets, and is also where you will find the Island's archaeological museum and Epta Martyres, a tiny church perched on a rock in the sea. An ancient settlement, Kastro was built into a citadel, with tightly-packed houses and defensive walls.
NIGHTLIFE Small bars can be found in Platis Gialos and other towns, but the heart of nightlife in Sifnos is the Steno, or alley, in Appolonia.
POTTERY Sifnos is known for it's ancient pottery culture and modern pottery industry alike. Workshops produce decorative pieces and items for daily use. Find a list of studios here: Sifnos pottery.
FOOD The birthplace of famous Greek Chef Nikolaos Tselementes, Sifnos offers delicious cuisine. Local specialties include revithatda (chickpea soup), kokkinisto (lamb or goat cooked in red wine and tomato sauce), chickpea patties, caper salad, and local manoura cheese. For anyone who will be on Sifnos September 7th, 8th, or 9th, there will be a Gastronomy Festival. Also worth tasting are the sweets from pastry shops in Appolonia and Artemonis. For caffeine, try Greek coffee and iced Frappe. Or for a caffeine-free Greek beverage, try mountain tea.
AND MORE... This website offers cooking classes, folk dance lessons, guided tours, and guided hikes: Sifnos Alternatives
The center of town is Syntagma square, the parliament building (where demonstrations sometimes occur), and the upscale neighborhood of Kolonaki where you can stroll and look at boutiques. Above Kolonaki is Lykabetus hill, which offers a nice hike and view, or a telepheric (cable car) that takes you up. Io's parents live nearby, at Dexameni square.
A very full day:
Visit Acropolis by subway (~2€) as early as your jet lag allows to avoid heat and crowds. On the way, you can stop at Syntagma station (without exiting the metro) to see excavated antiquities discovered while digging the metro.
Have lunch at and explore the Acropolis museum, which has a great view, good food, AC, and impressive marbles. Note that cabs are quite cheap (3.5€ for ~5minute ride) if you don't want to walk.
Stop by the Temple of Olympian Zeus and then wander through Plaka on your way to the Museum of Greek Folk Musical Instruments (a little-known gem, closes at 5pm). You are next to the Temple of the Winds, the Roman Agora, and Hadrian's Library, and a short walk to the Ancient Agora and the Temple of Hephaestus.
Some museums:
A favorite is the Museum of Cycladic Art, with very old pre-Hellenic (3500 ago) sculptures and an upscale cafe. It is very close to the Benaki museum. Both are medium-sized and can be done back to back.
The National Archeological Museum is a bit away from town center (cab) very large (days to see it all) but absolutely worth a visit. Make sure to see the Antikythera mechanism, the first analogue computer from 70BC.
There are various walking tours which we've heard are interesting, some are donate what you want. More information is online and on TripAdvisor. A friend did a full moon tour that ended up in a bar till 5am...
If you have a few extra days, consider renting a car and exploring the Peleponese. Let us know your dates if you want help connecting with others who are also interested in doing this.