WaterSportDirectory.com - A guide and resources web directory that offers all things water sport about such as swimming, diving, kitesurfing, sport fishing, underwater, water polo, windsurfing, water skiing & wakeboarding.
Passage Water Ski Center
Located in Poros Island, one-hour trip from Athens. Open all year round and practise water ski from complete beginners to professional slalom skiing.
http://www.passage.gr/
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Ververoda Bay WaterSki Center
Located near Porto Heli, on the east coast of southern Peloponese, Greece. Offers slalom, tricks and jumping school and more.