Two castle villages on Santorini, Pyrgos and Emporio
On Santorini a kasteli can be an entire fortified settlement. A walk through Pyrgos and Emporio makes that easy to see. In one village the approach climbs to an exposed hilltop. In the other, buildings crowd close enough to join across the lane overhead.

What survives of the castle at Pyrgos?
Start in the main square and climb through the village toward the Kasteli. The hill gave the settlement a long view across the fields and sea, and defenders could limit entry to a single gate. The gate, known as the Portara, has disappeared. The church of Agia Theodosia near its former position gives you a landmark to find on the way up.
Which part of Emporio should I walk through?
First pick out the Goulas, the square Venetian tower near the entrance to the village. Then head into the Kasteli itself. Inside, take time to follow the lines of the houses above eye level. Outdoor stairs rise almost vertically and covered bridges cross between buildings. These details explain how closely people once lived together inside the fortified area.
How do the two visits fit together?
Use Pyrgos for the broad view and Emporio for a closer look at how a defensive settlement worked at street level. At Pyrgos, notice how much of the surrounding land you can see from the hill. In Emporio, stop just inside a vaulted lane and look back at how little of the route ahead a newcomer could have seen.