We got from our Athens accommodation to Santorini via a series of trains and buses, each more crowded than the last (apparently half the population of Greece resides in Athens), and then, finally, a ferry. Ahead of us the entire way was a pair of girls with bags comparable in size to our own, and it turned out they were, of all things, Canadian naturopaths headed to the island too, so we sat with them on the ten-hour ferry ride and chatted and slept.
I think what's so amazing is the scale; there's just so much space before you, right there, cradled by the island. The caldera might be a bath, and the gigantic cruise ships and ferries breezing through it toys. You know how big those ferries are because you arrived on one, and there they are, tiny as snails leaving white trails of foam instead of slime.
Your eyes can't even comprehend the space. The water doesn't actually look that far away below you, but then you see people moving around down there barely visible they're so tiny and you realise how high up you really are.
On our second go past the man's cafe, we were ensnared by the view it offered and decided to take a seat.
The next day I think we just swam and lazed again all day until we went into Fira for delicious pita kebabs and ice cream, and then iced teas on the caldera. Basically all our days followed this pattern of sleeping in, lazing and swimming until hunger drove us into Fira for food and drinks on the caldera. It was nice. After that we just went back to the hotel and hung around the pool reading (I finished Cloud Atlas here) till our lift to the dock.