What's the must-see thing in Mykonos?

Delos, not Mykonos Town. Every Cycladic island has white churches and sunset cocktails. Only Mykonos sits 30 minutes by boat from a 5,000-year-old city that served as the religious center of the ancient Aegean. The ferry from the old port currently costs roughly €22 round trip and tends to leave between 9am and 10am depending on the season. Book a day ahead between June and September or you'll likely watch the boat pull away without you. The site takes 2 to 3 hours at a steady pace. You'll walk past the Terrace of the Lions, where 5 marble originals from the 7th century BC once faced the Sacred Lake. The replicas stand in their place now; the originals sit inside the Archaeological Museum of Delos, open since 1904. In the House of Dionysus, floor mosaics have held their pigment for over 2,100 years, the tiger's stripes still sharp enough to photograph. The heat is the real challenge. There's almost no shade on the island, and by 11am in June the white marble throws back enough glare to sting your eyes. Bring 2 litres of water and a hat. The small on-site café is overpriced and undersupplied.

Back on Mykonos, Paraportiani is the single building worth planning around. The church sits at the edge of the Kastro neighborhood in Chora, and it looks like five chapels melted together over centuries, which is more or less what happened. Construction started in 1475 and the upper chapel was added roughly 200 years later. The walls have been whitewashed so many times that every corner has softened into a curve, and in late-afternoon light the whole structure turns a warm cream against the deep blue behind it. Morning is better for photos. By 5pm the tour groups thicken and you're shooting over someone's selfie stick. The walk from the old port takes about 4 minutes. No entry fee, and the interior is usually locked, so this is an exterior visit. The Archaeological Museum of Mykonos sits a 6-minute walk east, founded in 1902. It holds Cycladic pottery and a 7th-century BC pithos with reliefs of the fall of Troy. Entry costs €4, a visit takes about 30 minutes, and the galleries are almost always empty.

Little Venice is the row of 18th-century houses at the waterfront in Chora where the balconies hang directly over the water. The name oversells it. This is not Venice. It's 200 metres of converted captain's houses, most of them now cocktail bars charging €14 to €18 for a spritz. That said, the thing people come for is real. Near 8pm in June, you sit with your feet almost at sea level, the Aegean slapping the stone beneath your chair, and the sunset drops behind the Kato Mili windmills about 100 metres to your south. The light goes from white to copper in about 20 minutes. Galleraki and Caprice are the two bars with the best direct waterline seats, and both fill up by 7:30pm. If you miss a seat, stand along the seawall instead. The view is the same and the drink is €14 cheaper. Mind you, the meltemi wind picks up here most evenings. Daytime highs reach 27°C in June, but the gusts drop the waterfront temperature to 20°C after dark.

A few things to skip if your visit is 2 or 3 days. The south-coast beaches, Paradise and Super Paradise, get heavy marketing, but they're beach clubs with €30 sunbed fees and music loud enough to hear from the water. If you want sand, Agios Sostis on the north coast has no sunbeds, no bar, and no road noise. The sand is coarse and the water stays shallow for about 15 metres, warm enough by late June to swim without wincing. One honest trade-off about Mykonos in general. Prices run 30% to 50% higher than other Cycladic islands for comparable quality. A taverna meal for two with wine in Chora runs €60 to €80. The same meal on Naxos costs closer to €40. You're paying for the name and the infrastructure, and whether that premium is worth it likely comes down to the Delos day trip. Delos is the only open-air archaeological site of its scale within day-trip range of any Cycladic island.