Kostas (SailinGreekWaters) Kostas is the owner of SAIL IN GREEK WATERS, a sailing yacht charter company, based in Athens, Greece. Sailing holidays is more than island hopping and it can be combined with more genuine experiences, offering sailors a true taste about the beauty of the Greek islands. Underwater adventures through scuba diving brings our guests closer to nature and the treasures of the sea. Our guests are welcome to sail the Greek islands and enjoy scuba diving in specialized trips to unique destinations and diving spots.