and into Guadalupe, a little hillside town overwhelmed by a fortified monastery. It was here that King Ferdinand and Queen Isabella gave Christopher Columbus the green light, thus kicking off the entire New World Spanish venture.

But that’s not what brings the coachloads in. It is the Virgin of Guadalupe, patron of the Spanish-speaking world. To see her, you must join a group, troll through the treasure-stuffed monastery (these monks clearly took Vows of Richness) to the church, where she is perched 25m high in the altarpiece. Then you come out and climb up the back of the altarpiece to a red marble chapel where a Franciscan chap swivels a frame round. Suddenly, the Virgin is staring not out over the church but into the chapel, and on your level. She’s 50cm high, black, swathed in pink and gold and has the Infant on her knee, like a ventriloquist with dummy.

Spanish matrons stopped chattering about their health, queued to kiss an image of the Virgin, burst briefly into tears, put money in a shoe box held out by the Franciscan, then returned to chattering. I dodged out just before the shoe box and walked around town, which is a lovely effusion of arcades, flowers and happy old Spaniards having post-devotional drinks round the fountain.

But I was keen to get back down to the plain and on to Medellín. Medellín! Birthplace of Hernán Cortés, the most famous conquistador of them all. I’d admired Hernán ever since, as a revolting youth in Mexico City, I’d developed a need for anti-heroes. I couldn’t wait to get to Medellín – it was going to be good, I thought.

It wasn’t. Medellín wasn’t bad – just uninteresting, and uninterested in Cortés. There was a statue in some gardens, but that was it. Perhaps locals had been cowed by political correctness – conquerors are not right-on – or perhaps they’d no time with all those fields to look after. At any rate, the village dozed in Cortés-free fashion.

I asked a bloke where Hernán’s house had been, and he directed me to the church. My Spanish could do with some improvement, perhaps. I went anyway. There was a funeral on. Now, like many towns and villages in Extremadura, Medellín gave its name to settlements across Latin America, including Medellín, Colombia – generally reckoned to be the Colombian drugs trade HQ. So I was intrigued to learn that the dead guy was called Don Julio Relledo Escobar. Escobar? I peeped inside the church and the mourners didn’t look like intimates of an international cocaine baron – but then, do they ever?

From here, I should have gone to Mérida. Everyone should. It was Roman capital of Lusitania, is stiff with monumental remains and boasts an outstanding Roman museum.

But I’d been before and, from afar, the place seemed a scrum of hoardings, cranes and half-grown apartment blocks. So, though my head said ‘Museum!’, the rest of me said ‘You’re joking!’, and won easily. All together, we swung south, excited to be back in the Extremaduran hugeness. Villages lay across distant summits like light reflectors. Cattle stood shadeless under a merciless sun. (Fabulous, I thought. Pre-roasted beef.)

I rolled into Zafra. Among my very favourite spots in Spain (which will be gratifying for councillors and inhabitants alike), Zafra, famed as a cow town, has had an October cattle fair for 700 years. Not that you’d ever guess. Tight, white and bright, with some pretty hotels (among them Hotel Huerta Honda, with its Andalucían rooms), it looks as if it should be beside the seaside, except that the sea is 160km south. I parked inside the town walls, walked round to the ducal palace, looked up and fell off the pavement. This was Spanish magnificence. The walls loomed gigantically, radiating authority, clearly keen for a chance to lick the modern world into shape. It dominated Zafra, like a rider among footmen.

Cortés stayed here pre-Mexico, and I followed him in. As you might expect, the whole caboodle – marble-pillared inner court, winding stone corridors, venerable bedrooms – has become one of Spain’s state-run Parador hotels. In such surroundings I fully expected to be hailed as ‘Don Antonio’. I wasn’t, but I checked in anyway, then bounced out to explore.

I couldn’t have been happier, weaving along the little streets, between townhouses studded with ceramics, and little butchers’ shops full of hams hanging like mandolins.

I stumbled across Baroque churches, news of Europe’s unofficial first chess champion – the 16th-century townsman, Ruy López de Segura – and a convent where nuns sell cakes through a hatch with a blank door. You put your money on one side and shout your order. A nun puts the cakes on the other side and swivels the door. You never see her face.

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