Spanish steppes: an epic hike across the wild plains of Extremadura

It’s autumn, however – when the dehesa woodlands glow in spectacular fiery hues – that is the best time for hiking in Extremadura.

This far-flung region was considered extreme long before the Romans tried to tame it with a chain of fortress cities along what would later become famous as the Via de la Plata, toughest of the pilgrim routes that lead to Santiago de Compostela. Not everybody can dedicate the six or seven weeks needed to walk the 620 miles (1,000km) between Seville and Santiago, but a week’s hiking through the wilderness landscapes and historic communities of Extremadura offers a compelling introduction to Spain’s least-known region.

While I had travelled often in this area in the past, I’d first developed a real appreciation of its diversity during a recent coast-to-coast walk from Gibraltar to Estaca de Bares (the most northerly tip on the Iberian peninsula). During that 700-mile solo hike, I’d slept rough – either in my hammock or on the stony ground – as I collected material for my book, Vagabond: A Hiker’s Homage to Rural Spain. I’d been thrilled as much by the rugged hillsides and ancient cork forests – home to lynx, deer and wild boar – as I had been by the seemingly endless plains, where the grass rippled under a hot breeze that brought to mind African savannahs.

While I averaged 22 miles a day during that midsummer hike, I would recommend an autumn departure and a far slower pace, allowing ample time to savour the best of backcountry Spain. The hike northwards from Mérida to Cáceres could easily be done in three days, but extending it for a further three (and a total of 90 miles) across more challenging terrain to the historic little towns of Cañaveral and Galisteo is a once-in-a-lifetime chance to savour Extremadura at its wildest. Navigation is easy because the Via de la Plata route is well marked, with either yellow arrows or the scallop-shell emblem of the pilgrimage. Mérida (easily reached by public transport from Madrid) is the logical launchpad for a walk through this historic heartland.

It’s hard to imagine that this sleepy provincial city, with a population these days of around 60,000, was once known as Emerita Augusta and boasted a garrison of 90,000 Roman soldiers. The typical stage for pilgrims from here is a relatively short 11-mile saunter to the village of Aljucén, so there’s time before you walk out of Mérida to buy the pilgrim’s passport, the document that will allow you to stay in municipal albergues (hostels). It costs €3 and is available from albergues and tourist offices along the route.

Landlocked Extremadura obviously isn’t famous for its beaches. It had been a highpoint of my hike, therefore, when I enjoyed a lazy afternoon swimming and sunbathing on a “beach”, two weeks after I’d last seen the Andalucían coastline. Proserpina Dam (less than two hours’ walk north of Mérida) has been a place of rest for wayfarers since it was built by Roman engineers 2,000 years ago. With its fringe of dusty pines and whitewashed villas, this shimmering sheet of blue water is more reminiscent of a scene from a Greek island.

Try to stifle your enthusiasm for getting back on the trail and take time instead for a leisurely lunch of grilled fish from one of the two chiringuitos (beach bars), which open all year, since less than three hours’ hiking remain, through the oak forests to the hamlet of Aljucén and your first night’s accommodation.

The Extremadura section of the Via de la Plata must be one of Europe’s most affordable hiking trips. In Aljucén, for example, pilgrims can get a dorm bed in Albergue San Andrés for €12 and a menú del día in the village bar for just €10. For an upgrade you can’t ask for better value than the lovely, four-star Termas Aqua Libera, which still boasts functioning Roman baths (with a discount for pilgrims).

During the next five days, distances increase steadily, but your stamina and walking fitness will also improve. From Aljucén it’s a 12-mile hike across the forested foothills of the Sierra de San Pedro to the town of Alcuéscar, where there’s an opportunity to experience a very poignant part of the pilgrim philosophy: the local monastery here offers dorms run on the donativo principal, where pilgrims are simply invited to pay whatever they can afford.

The following day’s route follows a gently descending path for 16 miles to Valdesalor, where you simply collect the albergue keys from the village grocery store and make yourself at home. (Again, there’s an affordable inn with private rooms if you’re looking for an upgrade.) There’s not much to keep you in Valdesalor, but it’s worthwhile getting on the trail early the next day anyway so you can enter the walled city of Cáceres in time for breakfast. Walking through the Puerto del Río gateway, built in the first century, it’s easy to imagine the awe with which these mighty citadels must have struck medieval wayfarers.

Having walked 45 miles since leaving Mérida, you could make Cáceres an honourable final stop after a three-day hike, but it would be a shame to stop now, right on the edge of some of Spain’s most evocative landscapes. For the next few days the hike becomes more challenging and the wilderness more unforgiving.

Long stretches of uninhabited hills mean there are important logistical considerations to take into account. For this reason, most pilgrims resist the temptation to spend the night in Cáceres: instead it’s recommended to continue to Casar de Cáceres, seven miles to the north and (with two albergues) the logical basecamp for your most challenging day’s hiking.

About 20 miles separate Casar de Cáceres from the village of Cañaveral. While the trail is spectacularly beautiful, these hills (with nothing but a few remote, sometimes abandoned, homesteads) are not to be underestimated. Take ample water (and perhaps a water filter) since there is nowhere to replenish supplies in the four hours it will take you to reach the Río Tajo and, if you want to avoid the midday heat, set off at first light. Sunrise brings a gentle breeze, driving the morning mist across the hillside like a flock of downy sheep. This part of the trail has been preserved as a Cañada Real, one of the seasonal migration routes along which precious herds of merino sheep were driven across the country in the middle ages. If a 20-mile hike is pushing the limits, consider sleeping at a hotel in Cáceres city and taking a bus to Cañaveral.

You’ll have been on the trail about five hours when Alcántara reservoir tempts you with a cooling swim and, three hours later, there’s a definite sense of achievement as you finally scuttle into Cañaveral’s rabbit warren of shady lanes. You’re unlikely to want to explore far this evening, but there’s a romantic appeal in peaceful plazas where storks clatter their bills producing a sound like tiles falling from the church steeple.

The final stage of this week-long trek leads for 17 miles through extensive cork, chestnut and oak forests that are connected via wildlife corridors with Monfragüe national park. You descend towards the wooded banks of the Río Alagón, passing fields where fighting bulls graze and black Iberian pigs forage for acorns.

Suddenly, the rearing granite bulk of the fortress village of Galisteo appears on the horizon, like the stone boat that, legend has it, supposedly brought the body of Saint James to Spain. Crenellated battlements form the impregnable hull, while a church steeple rises like a ship’s stocky mast. A few whitewashed buildings cluster below the walls like a rolling bow wave.

Sitting on a sunny terrace sipping Cruzcampo and savouring locally cured serrano ham, you might gratefully celebrate the end of your 90-mile hike (and from here you can catch a bus back to Cáceres then a train to Madrid). It’s more likely, however, that you’ll start pipe-dreaming about the fact that just three more days would take you to the provincial border with Castilla y León, the threshold of still more Spanish backcountry adventures.

Vagabond: A Hiker’s Homage to Rural Spain by Mark Eveleigh is published by Summersdale (£10.99). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply