The author's mission - "to sift out the ancient, perverse and eccentric from the new, nice, and normal" - took him from coastal plain to mountainous peak. It also took him, often, by surprise. For the customs and rituals of Spain linger on in both likely and unlikely corners of the country, beguiling and obstinate, they defy the Spain of the tourist trail, providing instead a key to the real heart of the country. Deep Spain has fiestas instead of Bank Holidays, tapas instead of MacDonalds. It celebrates ritual pig-killing and not political correctness, and in places, has not changed for hundreds of years. Participating in the ancient customs of matanza, romeria, and trashumancia, Paul Richardson migrates with the sheep to winter pastures, stays in a 13th-century monastery and walks on a pilgrimage in the name of one of the many competing Virgins that pop up all over Spain. Enduring more than a little hardship and suspicion, he visits prehistoric-looking structures last inhabited in 1992, meets and alchemist who eats stone, samples food that translates as "wrinkly potatoes with spicy wet stuff" and embarks on a five-day trek with hostile, swearing shepherds.