Ask anyone who has done a round of tapeo through Pamplona’s Casco Viejo, and Cervecería La Mejillonera comes up as a fixture: the standing-room bar on Calle Navarrería where the entire menu is mussels, patatas bravas, and a fried calamari sandwich. Most guides treat it as a one-off Pamplona institution, the kind of place that grew up organically in this specific corner of the Old Town and nowhere else. It shares that shellfish-bar instinct with spots serving navajas trucked in overnight from Galicia, each moving fresh Atlantic shellfish into the city by the same inland logistics.
That’s not what it is. The bar on Calle Navarrería, 12 is one of six sibling locations, split today between two branches of the same extended family, all descended from a single Cervecería La Mejillonera that opened in Valladolid in 1967. This same address already turned up in Encierro’s piece on pimientos de Padrón, cited there as one of the verified bars anchoring Pamplona’s old town tapeo route, though pimientos themselves aren’t on this particular menu, which stays narrower than that. Missing that fact doesn’t just miss a piece of trivia. It misses why the format works the way it does: a deliberately narrow menu, a standing-only floor plan, and a shared purchasing arrangement across cities that keeps prices low enough to make it a genuine fiesta-week workhorse rather than a novelty stop.
This account draws on the bar’s own institutional history, a first-person interview with a member of the founding family who runs the branch that includes Pamplona’s location, and the documented history of Navarrería itself as one of the city’s three original medieval boroughs.
The Menu Is Narrow on Purpose
Walk in and the offer is short: mussels, patatas bravas, and a fried calamari sandwich (bocadillo de calamares). That’s it. There’s nowhere to sit. Customers eat standing at the bar or at the high counters, order shouted to the kitchen, plates cleared fast to make room for the next round.
The mussels come in five preparations: con tomate (known across every branch of the business as “tigres” and the single best-selling version company-wide), steamed with lemon, vinaigrette, spicy mayonnaise, and marinera. The patatas bravas sauce is not generic. It was adapted from the spicy sauce served on calamari sandwiches at El Calamar Bravo, a well-known Zaragoza bar, by the man who would go on to found La Mejillonera.
The narrowness is deliberate. A member of the founding family, interviewed by the San Sebastián food outlet Pintxos Donostia, put it plainly when asked about the philosophy behind the business: fewer products, run at high volume, kept cheap enough that customers keep coming back. It’s the same logic that makes standing bars with short menus dominate Pamplona’s Old Town during fiesta week, when speed and turnover matter more than variety.
The Real Origin Story: Valladolid, 1967
The founder was Javier González Abadía, from Zaragoza. Before starting his own business, he worked for a period at El Calamar Bravo, the Zaragoza bar whose sauce would later shape La Mejillonera’s own patatas bravas. Using an inheritance from his grandfather, and combining El Calamar Bravo’s concept with that of a Madrid mussel bar called La Ría, González Abadía opened the first Cervecería La Mejillonera in Valladolid in 1967, the home city of his girlfriend at the time. The mussel recipes came from the Madrid bar; the bravas sauce came from adapting his former employer’s calamari-sandwich condiment.
This 1967 founding date is confirmed independently by the business’s own institutional history and by a direct, on-the-record interview with a member of the founding family, both agreeing on the year without citing each other. A separate secondhand account references an uncited 2012 newspaper profile placing the founder in Valladolid from 1970 instead. Because the 1967 date carries two independent, first-hand confirmations against one secondhand paraphrase, this account treats 1967 as the founding year.
What happened next explains why there are now six branches instead of one. González Abadía brought in a former colleague from El Calamar Bravo to run the Valladolid location as an equal partner while he opened a second branch in Burgos. When that partner had built up enough capital of his own, he asked to open a Mejillonera in Zaragoza instead, González Abadía agreed, and the Valladolid business went back to the original partner. The two men’s companies formally split, but the families stayed close. Today one branch runs Zaragoza, Burgos, and Valladolid. The other, the branch that includes Pamplona, runs Donostia/San Sebastián, Pamplona, and Logroño. A seventh location in Palencia belongs to a further-splintered branch of the same extended family. As the interviewed family member described it, the arrangement isn’t a franchise, but the shared purchasing between branches functions like one.
Who Actually Runs Pamplona’s Branch
Pamplona’s location, along with Donostia and Logroño, is run by two brothers: Armando and Alfredo Escudé. In the 2020 interview, Armando described taking over the Pamplona business with his brother after training under their family, Armando at 25 and Alfredo at 24. Their father and uncle had originally opened the family’s first location, in Donostia, together in August 1974. Armando’s father died in 1986, after which his uncle ran the business and later trained the next generation, including Armando, to take it over.
That family history matters for a simple reason: it’s the difference between a chain run by anonymous ownership and a small, three-city operation still run day to day by people who grew up in it. The interview makes that point directly when it notes the bravas sauce itself differs slightly between branches, something a true corporate franchise would never allow.
Navarrería: The Neighborhood, Not Just the Address
Calle Navarrería, where the bar sits, runs through Navarrería, the oldest of Pamplona’s three original medieval boroughs, alongside San Cernin and San Nicolás. The three boroughs, each with its own government and frequent rivalries in the medieval period, were unified into a single city in 1423 under King Charles III. Navarrería corresponds to the earliest, Roman-era settlement at the core of what is now Pamplona’s Casco Viejo.
This isn’t a stretch connection added for flavor. Calle Navarrería is a documented tapeo corridor in its own right, with other established bars and eateries on the same short stretch of street. The bar’s location inside this specific borough, rather than in the newer Ensanche districts to the south, places it inside the same historic core that the encierro itself runs through every morning of San Fermín.
What Visitors Should Know
The bar has no seating. Budget for standing at the bar or the high counters, ordering a few rounds of mussels and bravas alongside a caña, the way locals order beer, rather than asking for a “cerveza.” Prices stay low specifically because of the high-volume, narrow-menu model described above; a few rounds and a beer typically run well under what a sit-down restaurant would charge for the same. During San Fermín, expect it busy at almost any hour bars are open, consistent with the rest of the standing-bar scene across the Casco Viejo, the same scene covered in Encierro’s piece on the sandwich mixto, another bar staple whose name changes depending on which city you’re standing in.
FAQ
Is Cervecería La Mejillonera a Pamplona-only bar?
No. It’s one of six current locations (plus a seventh in Palencia) descended from a single bar founded in Valladolid in 1967, now split between two branches of the same extended family. Pamplona’s location is run by the branch that also runs Donostia/San Sebastián and Logroño.
What does La Mejillonera serve?
Three things, by design: mussels in five preparations (tomato, steamed with lemon, vinaigrette, spicy mayonnaise, and marinera), patatas bravas with a sauce adapted from a Zaragoza calamari bar’s recipe, and a fried calamari sandwich.
Where is Cervecería La Mejillonera located in Pamplona?
Calle Navarrería, 12, in the Casco Viejo, inside Navarrería, the oldest of Pamplona’s three original medieval boroughs.
Who founded La Mejillonera?
Javier González Abadía, a Zaragoza native who had worked at El Calamar Bravo, opened the first Cervecería La Mejillonera in Valladolid in 1967, combining that bar’s sauce with the mussel recipes of a Madrid bar called La Ría.
Every article on the Encierro blog is authored or reviewed by active bull runners with direct experience in Pamplona.