Akrotiri

Structurally yes, and in one respect emphatically not. Both were buried by a volcanic eruption and both preserve streets and standing buildings in a way ordinary archaeology does not. But almost no human remains have been found at Akrotiri, which is generally read as the town having been abandoned before the end. How much warning the population had is argued over rather than settled.

No. The major wall paintings from Akrotiri are in the National Archaeological Museum in Athens and in the Museum of Prehistoric Thera in Fira, not in the excavation itself. What is at the site is the architecture — streets, staircases, multi-storey houses and storage jars in place — which is a different and equally good reason to come, provided you know before you arrive.

Yes, entirely, by a modern bioclimatic roof over the whole excavation. That makes Akrotiri the one significant sight on Santorini that is out of the sun and unaffected by weather, which is why it is worth deliberately scheduling for the hottest part of the day rather than the coolest. Walkways run above and through the streets.

It is about fifteen kilometres to the southern end of the island. Most visitors drive or take a taxi, and buses run from Fira to Akrotiri village leaving a short walk to the site. It sits close to Red Beach, so the two are usually done together — though the beach is exposed and the site is not, which is worth ordering around.