Santorini or Mykonos?

Greece's two headline islands get booked interchangeably, and that is how holidays go wrong. Santorini and Mykonos share white paint, blue domes and ferry links, and almost nothing else.

Short answer: Santorini for scenery, romance, wine and photographs; Mykonos for sand, swimming and nights out. Couples and first-timers in Greece tend to choose Santorini, groups and beach-first travellers Mykonos.

What Santorini actually is

Santorini is a drowned volcano, and everything famous about it hangs on the caldera rim: the cliff villages of Fira and Oia, the sunset crowds, the hotels carved into pumice with infinity pools facing the void. It is a landscape experience, arguably the most dramatic in the Mediterranean, plus real substance underneath: the buried Bronze Age town of Akrotiri, volcanic wine that grows in coiled baskets, and black and red beaches that are interesting rather than beautiful.

The honest catches: it is the more expensive island, the sunset zones are genuinely crowded in season, and swimmers get striking-but-stony shores rather than soft sand.

What Mykonos actually is

Mykonos is flat, brown and windmill-dotted, and nobody comes for the landscape. They come for the best beach scene in Greece: a southern coast of genuinely sandy bays running from family-calm to full beach-club spectacle, and a nightlife that runs until sunrise. Mykonos Town is a gorgeous white maze built to confuse pirates and now perfectly confusing visitors, with Little Venice's waterline bars as the postcard.

The catches mirror its strengths: peak-season prices rival Santorini's, quiet is scarce in July and August, and beyond beaches and town the sightseeing list is short, though the sacred island of Delos, one of Greece's great ancient sites, is a short boat hop away.

The decision in one paragraph

Choose Santorini for scenery, romance, wine and photographs you will frame; accept crowds at sunset and pebbles underfoot. Choose Mykonos for sand, swimming, energy and nights out; accept wind and a thinner sightseeing menu. Couples and first-time Greece tend Santorini; groups and beach-first travellers tend Mykonos.

Or refuse the question

The islands are a couple of ferry hours apart, so a split week does both honestly. And the quiet third answer is Naxos between them: bigger, greener, cheaper, with better sand than Santorini and better sights than Mykonos, which is why returning visitors keep ending up there.

Either way, pack the beach kit, book sunset-zone rooms early, and check the when-to-go pages - September keeps the warmth and sheds the worst of the crowds on both islands.