Antica Pizzeria Port'Alba opened in 1738 as a stall, not a restaurant. Its pizzas left the oven on the heads of street sellers, stacked inside tin stoves, and were sold by the slice to customers who paid eight days later. Seating arrived only in 1830. The ground that Naples Pizza Walking Tour tours cross in the Historic Center carries that older commerce: a food designed to be eaten standing, folded, in motion. The street grid beneath those footsteps is Greek, then Roman. Via dei Tribunali follows the decumanus maior; Spaccanapoli cuts the decumanus inferior in a line visible from the Vomero hill above. Tomatoes reached southern Italy in the sixteenth century and were grown as ornament before anyone trusted them as food. Cooks in the poorest quarters put them on dough anyway. By the 1830s the city counted dozens of pizzerie, most of them single rooms with an oven at the back. In 1889 Raffaele Esposito of Pizzeria Brandi was credited with the pie of fior di latte, tomato and basil named for Queen Margherita of Savoy, a story retold on every Naples pizza tour and still disputed by local historians. Formal recognition came late. UNESCO inscribed the Historic Center on the World Heritage list in 1995, and in 2017 added the art of the Neapolitan pizzaiuolo to its register of intangible cultural heritage: the gestures, the dialect of the counter, the sixty to ninety second bake in a wood-fired oven. The Associazione Verace Pizza Napoletana, founded in 1984, fixes the remainder — San Marzano tomatoes, type 00 flour, a dough of water, salt and yeast, a raised and blistered cornicione, a centre no thicker than three millimetres. Those criteria are what a Neapolitan pizza tour is implicitly testing, oven by oven. The craft is inseparable from the architecture that holds it. Marble counters worn into shallow dips, majolica tiling, bassi opening straight onto the lane, ovens of Vesuvian tuff and volcanic sand fired continuously since before unification. Fried pizza, cuoppo cones of anchovy and courgette flower, sfogliatella and tiramisù occupy the same handful of streets, often the same doorways. Naples Pizza Walking Tour tickets cover ground rather than a single address, because the subject will not sit still inside one building. It belongs to the Quartieri Spagnoli, to the Pendino, to the lanes behind Port'Alba, and to the queue that forms at an oven door long before the bricks are hot.