Archipelago Map (www.archipelagomap.dk), VisitFyn (www.visitfyn.com) and Danish Archipelago (www.detsydfynskeoehav.dk) outline numerous activities including sea kayaking, windsurfing, angling, sailing, scuba diving and cycling, and give useful contacts.
For hikers, one of Funen's headline acts is the 220km Øhavssti (Archipelago Trail), a long-distance walking trail that snakes across southern Funen, northern Langeland and Ærø. It's divided into seven 25km to 35km sections, each covered by a free map-guide, available in Danish, German and English-language versions from local tourist offices or to download at www.visitodense.com/ln-int/funen/natural-areas/south-funen-archipelago-trail. You can also buy a more detailed 180-page guidebook covering the whole lot.
Vagabond Tours (www.vagabondtours.dk) offers six-night, seven-day packaged walk programs ferrying your luggage to the next accommodation as you hike (5050kr per person, minimum two people).
Submerged shallow-water Stone Age sites off western Langeland and close to Svendborg are relatively easily accessible to divers or even snorkellers. For experienced green-water scuba divers, wreck-diving on a scuttled former ferry west of Svendborg is a particular attraction. Regional dive sites are mapped on www.dyk-sydfyn.dk and Odense's Diving 2000 rents gear and organises trips.