‘You’d better write it down for him,’ said Hisham. ‘Oh, I forgot. You don’t read in England either, do you? So what do you do, English Robert?’

Ghalib said, ‘There are only two jobs in England. Farmers and whores.’

Robert said tightly, ‘Watch your mouth, pretty boy. My mother was English.’

‘So what kind of plough did she drive?’

Moraima stood between them hastily. ‘That’s enough. You’re like children - like all men! Come on. Let’s go into the mosque, and be respectful with it.’

So Robert entered the great mosque, with Moraima at his side, the stone floor cold under his bare feet, and the two boys sniggering at his back.

But in the mosque’s calm spaces, he soon forgot all about the boys.

It was like walking into a forest of slim pillars, linked by arches as delicate as the fronds of palm trees. Moraima said there were more than a thousand pillars in this one building. There were people walking everywhere, respectful, barefoot. Not a priest, or rather an imam, to be seen. The building was full of light, coming from windows and arched doorways, a light turned golden by reflection from the stone. Every way he looked the lines of pillars led his gaze away, deeper and deeper, until he saw walls adorned with inscriptions in beautiful Kufic script, words he could not read but which exhorted the faithful to raise their hearts to Allah.

He was grateful when Moraima’s hand slipped into his, for he felt he would soon be lost.

‘What are you thinking?’ Moraima asked softly.

‘That it’s beautiful,’ he said. ‘And that I don’t understand it. Of course I could say the same about you.’

She ignored the clumsy compliment. ‘It isn’t so hard. There is a central axis leading to the Mihrab. That points the way to Mecca; there the imam calls the faithful to Friday prayer. But you may pray wherever you like. The priests don’t get in the way here. My father says it’s a “different geometry of worship” from the Christian.’

‘This is nothing like a Christian church.’

‘Well, no. Christians build their churches as Romans once built their basilicas. That’s what my father says. The first emirs of al-Andalus started with nothing. They borrowed ideas - the round arches of the Romans, for instance. They even reused what the Romans and the Goths had left behind.’ And she showed him how many of the columns, of jasper and marble, were subtly different, in their proportions, their capitals; they were Roman and Gothic relics.

‘The arches are meant to look like the branches of palms,’ Moraima said. ‘It is an oasis in stone.’

‘Yet it’s centuries since your people came from the desert.’

‘Yes. We were thrown down here and changed. Isn’t it funny? Now we are not African any more, but not European - just us, something different in the world . . .’