The village of Oia in the island of Santorini is one that is very much photographed. A picturesque village of blue-domed churches, white houses and tiny alleyways huddled on the hillside overlooking the volcano. Oia is also famous for its photogenic sunsets. What is the caldera? That is one question I had when I started reading about this island and the said term kept coming up. The caldera is the water-filled cauldron that lies off Santorini and was created in 1450 BC when a huge volcanic eruption blasted through the once circular island, creating its current crescent shape.