These days we tend to think of borders as dividing lines superimposed on the land, more or less absolute, often fortified with loops of razor wire. The region between the Aegean and the Black Sea that now straddles Turkey, Bulgaria and Greece has seen no shortage of fences. But it has also always been a place of overlap and liminal encounters, between cultures and faiths, shepherds and soldiers, refugees and smugglers, this world and the next.

The poet Kapka Kassabova’s entry point to the border zone is her own childhood in Bulgaria under communism and the displacements that followed it, to New Zealand with her parents and eventually to the Scottish Highlands; the journey she makes in this passionately lived book is internal as well as geographic. She begins on the ‘red Riviera’, the Black Sea beach where she spent childhood summers among spies and sun-seekers from across the Eastern Bloc. Some were there to enjoy ‘totalitarian tourism’, others to risk their lives trying to cross to Turkey, by sea on dinghies and inflatable mattresses or on foot through the forested Strandja mountains, where a sign on the electric fence in Russian and German warned them to turn back.

Returning as an adult, she fulfils her longing to cross that forbidden border, and on her circular voyage through the Strandja, the plains of Thrace and the Rhodope mountains, she quickly discovers how richly history rhymes. The region has been both battlefield and a place of passage since