Volcanic beaches with easy entry, one great ruin, and a lot of stairs to plan around.
Perissa and Perivolos
Kilometres of black sand with shallow, calm water and sunbeds in front of tavernas. The sand gets scorching by eleven — bring shoes.
Akrotiri excavations
A Bronze Age town under a modern roof, with shaded walkways and preserved streets. Good for ages seven up; about an hour inside.
Museum of Prehistoric Thera
Small, air-conditioned and mercifully brief — frescoes and gold from Akrotiri, forty minutes in Fira when the midday heat wins.
Caldera boat trip
Half-day catamarans stop at the volcano crater and the hot springs. Choppy after lunch, so take the morning departure with younger children.
Steps, heat and naps
Fira and Oia are stair towns — carriers beat strollers everywhere. Base yourself flat in the south, nap at two, eat from seven.