When, and by what route, did farming first reach Europe? A terrestrial model might envisage a gradual advance around the northern fringes of the Aegean, reaching Thrace and Macedonia before continuing southwards to Thessaly and the Peloponnese. New dates from Franchthi Cave in southern Greece, reported here, cast doubt on such a model, indicating that cereal cultivation, involving newly introduced crop species, began during the first half of the seventh millennium BC. This is earlier than in northern Greece and several centuries earlier than in Bulgaria, and suggests that farming spread to south-eastern Europe by a number of different routes, including potentially a maritime, island-hopping connection across the Aegean Sea. The results also illustrate the continuing importance of key sites such as Franchthi to our understanding of the European Neolithic transition, and the additional insights that can emerge from the application of new dating projects to these sites.