The oddity is a leftover of medieval conquest. In the thirteenth century, as the Christian kingdoms pushed south, this rugged pocket of highland was folded into the newly formed Kingdom of Valencia by James I of Aragon, even though the country immediately around it ended up in Aragon and Castile. The frontier drawn in that era was never smoothed out, and the corner simply kept its allegiance while the map hardened around it. Centuries of administrative reform came and went, and still the Rincón held to Valencia - a border decision made by kings and crusaders, preserved almost by accident into the present day.

The land is bound together by a single river. The Turia rises in these interior highlands and gathers the Rincón's scarce water as it goes, the lifeline of an otherwise dry and stony country. It is the same river that, more than a hundred kilometres downstream, reaches the sea at the city of Valencia itself - the very capital this exclave belongs to. There is a quiet poetry in that: the corner may be stranded on the map, but the water running past its villages flows all the way home. Follow the Turia far enough and the isolated highland and the distant Mediterranean city turn out to share the same current.

The comarca gathers seven municipalities, of which only the capital, Ademuz, holds more than a thousand people. The others are small stone villages clinging to hillsides above the Turia. The most dramatic is Castielfabib, crowned by a fortress-church that dominates the town from its rocky summit; its castle, of ancient origin, was taken by Peter II of Aragon in 1210 after a long siege before the region passed to Valencia. These are places built for a frontier - defensible, watchful, perched high - and their silhouettes against the highland sky still read as the strongholds they once were.

Today the Rincón is quiet to the point of emptiness. It is high, rural country, and like much of Spain's interior it has thinned over the past century as people left for the cities. Villages that once grew important enough to break away from Ademuz - Vallanca, Puebla de San Miguel, Casas Altas, Casas Bajas - now count their residents in the hundreds or fewer. What remains is a landscape of almond and pine, cold clear winters, and enormous silence, the kind of place travellers cross and remember. Its emptiness is not neglect but a slower rhythm, a corner of Spain that time has left, for better and worse, largely to itself.

For so small and remote a place, the Rincón takes unusual care of its own memory. It supports a cultural institute devoted entirely to studying the comarca, which since 1995 has published a quarterly journal named ABABOL, and local historians have filled volumes on the art and architecture of towns like Ademuz, Castielfabib, and Vallanca. That instinct to document is a kind of quiet resistance. A community that might easily have faded into the blank spaces of the map has instead insisted on being known, chronicling its churches, its castles, and its dwindling villages so that the corner's long, stubborn story will not vanish with the last of its people. Isolation, here, has bred not indifference but a fierce sense of self.