Photo credits (Wikimedia Commons, Creative Commons licences):
Santorini — LBM1948, CC BY-SA 4.0 · Mykonos — Bgag, CC BY-SA 3.0 · Naxos — Bgabel, CC BY-SA 3.0 · Paros — Wikimedia Commons, CC BY-SA 4.0 · Milos — dronepicr, CC BY 2.0 · Ios — Flickr upload bot, CC BY-SA 2.0 · Sifnos — Wikimedia Commons, CC BY-SA 4.0 · Serifos — Wikimedia Commons, CC BY-SA 3.0 · Folegandros — Wikimedia Commons, CC BY-SA 3.0 · Rhodes — Wikimedia Commons, CC BY-SA 4.0 · Kos — Wikimedia Commons, CC BY 3.0 · Corfu — Amethyst forest, CC BY-SA 4.0 · Zakynthos — Badgernet, CC BY-SA 3.0 · Kefalonia — Flickr upload bot, CC BY 2.0 · Lefkada — Wikimedia Commons, CC0 · Chania — dronepicr, CC BY 2.0 · Heraklion — Wikimedia Commons, CC BY-SA 3.0 · Skiathos — dronepicr, CC BY 2.0 · Hydra — dronepicr, CC BY 2.0 · Samos — Wikimedia Commons, CC BY-SA 3.0 · Chios — Wikimedia Commons, CC BY-SA 3.0 · Thassos — Wikimedia Commons, CC BY-SA 4.0 · Patmos — Wikimedia Commons, CC BY-SA 4.0 · Karpathos — Volodymyr Vlasenko, CC BY-SA 3.0 · Skopelos — Wikimedia Commons, CC BY-SA 3.0 · Aegina — Runner1928, CC BY-SA 4.0 · Syros — Panoramio upload bot, CC BY-SA 3.0 · Spetses — Flickr upload bot, CC BY 2.0 · Amorgos — Wikimedia Commons, CC BY-SA 4.0 · Poros — Wikimedia Commons, CC BY 2.5 · Kythnos — Wikimedia Commons, CC BY-SA 3.0 · Astypalaia — Wikimedia Commons, CC BY-SA 4.0 · Anafi — Wikimedia Commons, CC BY-SA 4.0 · Symi — Panoramio upload bot, CC BY-SA 3.0 · Ikaria — Armenistis View Studios, CC BY-SA 3.0 · Nisyros — Wikimedia Commons, CC BY 3.0 · Kalymnos — Wikimedia Commons, CC BY-SA 3.0 · Agkistri — Wikimedia Commons, CC BY-SA 4.0 · Athens — Jebulon, CC0 · Thessaloniki — Haneburger, CC BY-SA 4.0.