I was born and grew up in Portugal, from which sunny idyll I paid yearly visits to Leicester to spend summer holidays with grandparents. To return to this industrial city at the heart of Middle England years later, and find it pulsing with Hindu, Sikh and Jain temples was one inspiration for Sacred Britain. Other seeds were sown when I followed in the footsteps of millions of medieval pilgrims across the salty sea cliffs of north Wales to drink from a holy rock pool below the high tide mark which, miraculously, was bubbling with clear, sweet water; and when I first observed the remarkable similarities between the faith displayed at religious shrines, and the ardent devotion shown by his followers at the tomb of Karl Marx. A sense of the sacred in 21st-century Britain, I realised, takes manifold forms and is to be found in unlikely places. Accordingly I set off on a quest for the sacred which took me from Orkney, north of mainland Scotland, to the southwest tip of Cornwall; and from the wilds of west Wales to the expanses of East Anglia. Time and again, I was astonished by what I discovered.