The Colossus of Maroussi by Henry Miller (1941) is the obvious starting point — a rhapsodic, slightly unhinged account of Miller's travels through Greece just before the Second World War. He barely visits Naxos, but he captures the quality of Greek light, the weight of mythology hanging over every landscape, and what it feels like to arrive somewhere ancient and be made small by it. Ignore the occasional pomposity; the wonder is genuine.
The Magus by John Fowles (1965) is set on a fictional Greek island that draws heavily on the Cyclades atmosphere — isolation, heat, the strange intimacy of island life, the presence of an ancient world just below the surface. It is a novel of games and illusions, and it uses the Aegean setting brilliantly as a place where ordinary rules stop applying. Read it before you go; it changes how you see the islands.
Cycladic Art: Ancient Sculpture and Ceramics of the Aegean by Pat Getz-Gentle is the serious companion to any visit to the Archaeological Museum in Hora. Cycladic figurines — those abstract marble figures with their folded arms and blank faces — are among the most haunting objects from the ancient world, and this book explains what is known and, more usefully, what remains mysterious about who made them and why. The Naxos museum has one of the finest collections.
The Penguin Book of Greek Verse edited by Constantine Trypanis (1971) is an anthology that runs from Homer to the twentieth century. Greek poetry, ancient and modern, is saturated with islands — Sappho's longing for Lesbos, the Odyssey's catalogue of Aegean landfalls, Seferis's bitter meditations on exile and return. Reading a few pages on a ferry crossing gives the sea a different weight.
Dinner with Persephone by Patricia Storace (1996) is a year spent living in Athens and travelling through Greece, written with precision and a fine eye for contradiction. Storace is particularly good on the way Greeks inhabit their mythological past — not as nostalgia but as an ongoing argument. It's the best modern travel writing about Greece, and the sections on island culture apply directly to Naxos.