Seville, proud of its beauty, has been so stung by Brown's contemptuous remarks in Digital Fortress, which is partly set in Spain, that the town hall this week invited the writer to visit the city to "renew his knowledge and revise his opinion".
The American author accuses the Andalusian capital of having hospitals that stink of urine, hopelessly inefficient phones and corrupt policemen. Most wounding of all, Brown attacks Seville's best-loved monument, the international symbol of its Moorish heritage: the 12th-century Giralda tower.
The Giralda, Brown sneers, "has stairs so steep that tourists have died here. This is not America, there are no warning signs, nor banisters, no advice about insurance policies. This is Spain. If you are stupid enough to fall, it's your own fault, independently of who built the steps."
It so happens that the Giralda, built as a lookout tower vital to the city's defences, has extremely wide and shallow steps, designed - so it's said - for Moorish guards to coax their horses up the tall tower and down again without their animals becoming spooked. "I can assure you that in the nine centuries since the Giralda was built, not one tourist has died because of the steps," Alfonso Rodriguez Gomez de Celi, spokesman for Seville's local government, told The Independent on Sunday last week.
The city where Velazquez made his first brush-strokes, and where Cervantes conceivedDon Quixote, does not take kindly to insults from a writer whose homeland was barely on the map while Seville commanded a mighty seaborne empire. "We understand that Digital Fortress - which was not very successful when it came out - is not a socio-political essay or a tourist guide. It's a novel, a work of fiction, which bears no relation whatever to the truth," Mr Rodriguez sniffed. "We take it as a literary device. The attractions of Seville are internationally known. We hope Mr Brown's readers are educated and intelligent people who can distinguish between truth and fiction."
Brown spent part of 1995 in Seville, where he studied art history at the university, and is supposed to have based his observations in Digital Fortress on personal knowledge - so he cannot even be said to be recalling the bad old Franco days. "What he says is completely untrue," Mr Rodriguez insisted. "We have very high-quality public services, and some of Europe's most advanced scientific research. We are one of southern Europe's most modern and developed cities."
The invitation is intended less as a rebuke than a gambit to promote tourism. "We hope that Dan Brown will accept our kindly meant invitation, and that his fans will flock to see for themselves the marvels of our city and to realise his fiction has nothing to do with the reality."
Elizabeth Nash's 'Cultural and Literary History of Seville' is published by Signal Books