The number everyone quotes about this roof is not published by anyone who would have to stand behind it

Five minutes north of the cathedral, on the far side of Via Laietana, there is a market with a roof that looks like a wave made of confetti.

It is the most photographed piece of twenty-first-century architecture in the old city, it is free to walk into, and almost nobody who goes for the roof walks to the back of the building — which is where the reason for all of it is.

The number we are not going to print

Start with the thing everybody says. The roof is made of 325,000 ceramic pieces in 67 colours.

We went looking for that, and here is where it lives. The 325,000 appears on mercatsantacaterina.com, a site that presents itself as the market’s official web. Its own legal notice identifies the owner as A.A.C. Mercat Santa Caterina — the traders’ association, a private body. It is not the Institut Municipal de Mercats, which is the city’s markets institute and the actual public authority for this building. The city links to it, which is how the figure travels.

The 67 colours we could not find published anywhere at all, including on that site.

What an institution does publish is the area. The Generalitat’s heritage record: the roof is externally coberta per un mosaic ceràmic de 4.200 metres quadrats amb els colors de les fruites i les verdures.

Four thousand two hundred square metres of ceramic, in the colours of fruit and vegetables. That is a real number with a heritage file behind it, and it is a better sentence than the one it replaces.

What the roof actually is

Enric Miralles and Benedetta Tagliabue, EMBT. The architects’ register dates the reform 1997–2005. Miralles died in 2000, five years before it opened.

The Generalitat’s description is worth having in your head while you look up: undulating lines that en alguns punts arriben a ser arcs parabòlics, carried on a wooden truss, lined in wood on the inside and in ceramic on the outside.

That is the part people miss from the street. From outside it is a coloured wave; from underneath it is timber, and it feels like a hall rather than a shed.

Opening date: the Generalitat says 10 May 2005. The Ajuntament, marking the tenth anniversary, called Saturday 9 May the official day. A one-day gap between two public bodies about a ribbon cutting, which is roughly the level of precision this city manages on its own recent history.

The first covered market, and a small quarrel about it

The market before this one was built for a specific social purpose. The Generalitat’s file says the plot was granted to the Ajuntament, which decided to build a market per afavorir el subministrament de queviures als sectors populars de la ciutat — to improve the food supply to the city’s working districts. The architects were Josep Mas i Vila and Josep Buxareu.

It opened in 1848, and — per the Generalitat and per the city’s own markets institute — it va ser el primer mercat cobert de la ciutat. The first covered market in Barcelona.

The MUHBA, describing the same building, calls it el segon mercat de Barcelona — the second market. Without the word covered.

The two are reconcilable: second in order of founding, after the Boqueria on La Rambla, and first to be roofed. But as written they are two different claims from two municipal sources, so if you use “the first covered market”, the citation is the markets institute or the Generalitat, not the museum.

A footnote for anyone who read our piece on the squares: Josep Mas i Vila is the same architect who built the neoclassical front of the city hall on Plaça de Sant Jaume — the man who, in 1852, also tried to have the Gothic façade round the corner demolished. He had a very busy decade in this neighbourhood, and not all of it was constructive.

The convent underneath

The name is not decorative. Before the market there was the Dominican convent of Santa Caterina, raised in the thirteenth century, and the MUHBA adds the detail that makes it matter: it was the primera seu del Consell de Cent, the first seat of the council that governed Barcelona.

The museum says it was demolished in 1835, malgrat la seva indiscutible vàlua artística — despite its indisputable artistic value — and calls it un dels convents gòtics més importants de la ciutat. The Generalitat says the land was occupied by the convent fins el 1837.

Two years apart, and neither file uses the word disentailment. The 1835 date sits exactly where you would expect it to in the history of the Spanish disentailments, and the churches of Barcelona were burned that July. But the heritage records give a date and a transfer of the plot to the council, not a legal category, and we are not going to supply one they did not write.

Something similar happened on La Rambla, thirteen years earlier and for the same reason, which is why there is a market where a convent was there too.

And four thousand years, at the back

Here is the part that justifies the detour.

The Miralles reform, says the MUHBA, va permetre fer importants excavacions arqueològiques a la zona. And what came up went far past the convent: remains that es remunten gairebé 4000 anys enrere, a l’edat del Bronze.

The new market keeps a space where that is explained, at the rear, with the remains of the convent left visible under interpretive panels. The Generalitat’s file confirms it: a reserved area where the old convent is exposed, with panels installed by the city history museum.

Santa Caterina joined the MUHBA’s network in 2007 — one of the eighteen buildings that make up the city history museum, and one of the free ones.

So the sequence under one roof is: Bronze Age, a Gothic convent that housed the city’s first parliament, an 1848 market built to feed the poor, and a ceramic wave from 2005. In a building most people photograph from the outside and leave.

Going

We are not printing hours — they belong to the market and they move.

Come for a weekday morning, not a lunchtime. It is a working market with a neighbourhood using it, which is exactly what the Boqueria has largely stopped being.

Walk to the back. Past the stalls, to the archaeological space. It takes four minutes and it is free, and it is the only place in this neighbourhood where you can see a convent, a market and the Bronze Age stacked in one view.

Look up from inside before you look at it from outside. The timber is the surprise.

It sits in a part of Ciutat Vella most itineraries skip — the streets of Sant Pere, Santa Caterina i la Ribera, on the far side of Via Laietana, which is also where the Casa dels Entremesos keeps the city’s giants and five minutes from the 1714 excavation under the old Born market. Between those three you have an afternoon that almost no visitor to Barcelona has.

Our Gothic Quarter walk stays on the cathedral side, told by an actor rather than recited, so this is deliberately a page about somewhere we do not take you — which seems the honest way to recommend it. The walkable order for the part we do cover is what to see in the Gothic Quarter.

The other municipal market everyone visits is the Boqueria, which has three times as many stalls and a written rule about how much of it is allowed to be a snack bar.