1) volcano in Greece 
[volcano] Kolumbo is an active submarine volcano in the Aegean Sea, about 8 km northeast of Cape Kolumbo, Santorini island. The largest of a line of about twenty submarine volcanic cones extending to the northeast from Santorini, it is about 3 km in diameter with a crater 1.5 km across. It was `discovered` when it breached the sea surface i...