At the beginning of this year, a few dozen eager primary-school students ascended the mountains near Leonidio, in Greece’s Peloponnesus, tape recorders in hand, to visit cliffside hamlets accessible only by narrow and impossibly steep roads. Tsakonian is considered the only descendant of Doric Greek, a classical Hellenic language last spoken more than 2,000 years ago around the military city-state of Sparta. Tsakonian managed to survive in this corner of southern Greece, whose hilly and rocky paths discouraged foreign occupiers and hindered contact with other regions.