Sierra wanderings

Walk towards the Garganta del Fraile near Serradilla (Martin Kelsey)

The Almonte River is marked, after four months of drought, by a belt of bleached dull grey pebbles, a fossilised watercourse, with two shrunken still pools as signals of what once was. Crossing the river from the south, the road climbs a sandy, conglomerate ridge to overlook a vast bowl of dehesa, a landscape stippled by innumerable encinas, the indomitable holm oaks of the Mediterranean savanna. It is rimmed by the southern edge of the Monfragüe syncline: the barrier of 500 million-year old quartzites, lichen-toned crags erupting from the flanks of evergreen oak cover. From the ridge I can see my destination, the village of Serradilla, lying at the foot of this rim and to the west of that most emblematic of the ruptures across the quartzite, where the great Tagus River cuts past the massive Peña Falcón cliff: the southern gateway of the Monfragüe National Park.

Serradilla is that typical half-forgotten outpost, a dense pack of mainly single-storey white-walled, terracota-tiled homes terraced along eccentrically-dimensioned cement streets, which if you looked from above, recall the logic of a spider's web, but at ground-level transform to a maze. Hardly a soul is encountered, but from some of the dwellings partially-raised shutters and colourfully-striped door-curtains suggested occupancy. From the main road which takes an oblique chord across the town and compromises its width as it searches out the least obtuse of routes, there are few signs of commerce, but down a side-street I quickly find a bar where I am cheerfully offered an ample pincho of tortilla to accompany my coffee.

Leaving the car at the edge of Serradilla I take a lane that strikes out parallel to the hillside above the village. I rejoice at the discordant continuation of the buildings either side of my route, the irregularly plastered walls and painted metal doors of sheds, workshops and garages: signs of a lived-in, worked-in village. This impression is reinforced as I enter the patchwork of stone-walled parcels of small-holdings that is typical of settlements here, precious assets for the people, sandwiched between the village and the vast latifundia of private estates. These dusty allotments are populated by Iberian pigs, a few chickens and donkeys, remains of the summer tomatoes wither and from a plot of water melons, with the globes of fruit dotted across the yellowing bed of leaves, a flock of Rock Sparrows twang as rise, their white-tipped tails flashing. The uneven stone walls offer perches for Black Redstarts. An arid paddock is criss-crossed by ant highways, dark seams across the textile-like mat of dried grasses, whilst a Hoopoe waddles in its curious clockwork gait.

The slope above Serradilla, fingered by small olive groves, is largely clothed by evergreen oak, patches of pines and the matorral of rock rose, with emergent rock outcrops. Over these dozens of House Martins pirouette, amongst them the darker, stockier Crag Martins, with stiffer, more-swift-like wings. As I watch, a swift does enter the arena, black and slender, until with a twist, its white band reveals its identity: a White-rumped Swift whose sojourn here extends well into autumn. I pause on the track, listening to Cirl Buntings rattling and looking south-east over the rolling dehesa with the bluish form of the Villuercas Mountains on the horizon, a good 75 kilometres away.

The track now boasts a mixed vegetation: wild olives, mastic and strawberry tree and, as if on cue, a Two-tailed Pasha crosses the path, a flight of strong stiff glides, before settling on a lichen-covered snag to take the sun. I climb on top of a stone wall to try to get an unimpeded view of this impressive butterfly, but the angle is wrong with only its rear end in view, But as the sun warms it, it opens its wings and I get a powerful glimpse of the pair of amber bands on the upper forewing, the yellow strip on the hind wing, sky-blue dusted markings and the white-rimmed pair of tails.

Partially hidden Two-tailed Pasha (Martin Kelsey)

I am led finally to the Friar's Gorge, where a stream flows between a narrow entrance through the ridge and a quartzite pillar stands like a cowled monk in testimony. Above me two Griffon Vultures circle, taking deep flaps as they turn, paddling the air. A contrast to the steadfast determination of a Black Vulture which glides above them, crossing my view on rigid, slightly bowed wings.

Approach to Mirabel Castle (Martin Kelsey)

From Serradilla I cross the ridge and approach the ruins of the castle of Mirabel, standing high on Acero hill. The present structure has dominated the skyline since the 15th century, an earlier fortress being destroyed by the Almohades two hundred years earlier. A small group of Griffon Vultures had found an updraught along the ridge and were joined briefly by a Spanish Imperial Eagle, gliding away from me, before turning with a shock of the emulsion-white leading edge of the wing. Below the castle on a wide sweep of land is a dehesa of cork oaks, more noble trees than the holm oaks. I walk through this parkland, flushing a Tree Pipit from the ground close to me and I watch it take a perch, longitudinally on a branch, tail-pumping as it stands and preens. Ahead of me a cork oak stands out even amongst its conspecifics, taller, with a canopy spreading 27 metres. This is the Padre Santo (Holy Father) oak, estimated to be 900 years old. It stands unaided, its foliage lush green and evidence of successive cork harvests on its boughs high above me. This plant has lived through the whole of the history of the castle above it, indeed as a sapling it would have searched for light through the shade of conspecifics that might have started their lives during Roman times: conceivably just two or three cork oak generations away from the present. As I rest beside the Padre Santo, a movement catches my eye. A Spotted Flycatcher had left the tree on a short sally and is now back on its perch, in chippy upright posture and alert for prey. For the flycatcher, this is a stopover on its long-distance migration to the tropical forest savannas of Africa - how many generations of flycatchers has this singular tree served?

Looking up into the Padre Santo cork oak, 900 years old (Martin Kelsey)