Greece boasts thousands of islands, spread across an enormous geographical area stretching from the Aegean to the Ionian sea. Four of Greece’s five island groups are prime charter areas: the Cyclades, the Saronic Islands, the Ionian Islands and the Dodecanese. Each group has its own unique character. In all of them, you can visit the more popular places, opt to sail off the beaten track, or do a bit of both. Everywhere, archaeological and geological attractions abound. Unless you have 10 to 14 sailing days, focus on one island group.