Caldes de Montbui

The stone lion’s mouth spits water at 74 °C, hot enough to brew tea. Stand too close and the cloud of vapour fogs your glasses; step back and you watch locals queue with plastic jerry-cans, filling up as if the petrol crisis had struck again. This is not a museum display – it’s the Font del Lleó, the town’s public tap, and the water has been flowing since before Barcelona had a cathedral.

Caldes de Montbui sits half an hour north of the Sagrada Família, but the commuter belt stops at Granollers; beyond that, the valley narrows and the traffic thins. At 203 m above sea-level the air is a degree or two cooler than the coast, just enough to make the thermal haze rising from drains and gutters feel theatrical. The Romans set up baths here in the first century AD; the stone they quarried is still stacked in the basement of the Museu Thermalia, blackened by two millennia of steam.

A walk that starts hot and ends medieval

Begin at the Roman baths on Carrer de Desgràcia. You enter through a 16th-century townhouse that was plonked on top of the caldarium; the ticket desk occupies what used to be the furnace room. Inside, the hypocaust floor is intact – narrow brick pillars that once let hot air circulate under marble tiles. The guide (Catalan with a smattering of school English) demonstrates the plunge pools: cold, tepid, scalding. Admission is €5; students half-price. The visit lasts 25 minutes, after which the streets themselves become the exhibition.

Follow the vapour. It leaks from gratings, curls out of laundry sinks, and drifts across Plaça de l’Església like dry ice at a school disco. The medieval quarter is a grid of two-storey houses built from honey-coloured sandstone. Iron balconies hold geraniums and drying swimming towels. At Carrer del Forn 15, Fika Brunch has wedged itself into an old bakery; they serve oat-milk flat whites and a “full Catalan” of butifarra sausage, scrambled eggs and tomato-rubbed toast. Prices hover around €9 for breakfast – cheaper than central Barcelona and the menu is bilingual.

Children usually make straight for the witch-shaped slide in Parc de la Portalera. The playground sits beside an open-air laundry basin where water arrives at 60 °C; elderly women still scrub shirts here, wielding wooden tongs that look like salad servers. British visitors photograph the scene in disbelief, then retreat when they realise the basin doubles as a communal bathtub on Sunday mornings.

Taking the waters without the fluff

There are two ways to get wet. The fancy option is Balneari Termes Victòria, a Modernista mansion built in 1895 for wool-mill owners with gout. Day passes cost €32 and include three thermal pools (32 °C, 36 °C, 40 °C), a steam cave and a freezing hosepipe that a therapist aims at your calves. Swim-caps are compulsory; buy one for €2 at reception. The place fills up after 13:00 with extended families celebrating birthdays, so arrive before 11:00 if you want a lounger.

The budget version is Espai Aquae, a municipal complex that looks like a 1970s leisure centre somebody forgot to knock down. Entry is €12, lockers take a one-euro coin that you never see again, and the main pool smells faintly of eggs. On the plus side, the water is identical – it comes from the same aquifer – and you can stay all afternoon. Both spas insist on silence in the steam rooms; Spanish grandmothers enforce the rule with the efficiency of Ofsted inspectors.

Beyond the steam: where the valley folds

If the afternoon turns hazy – common in May and October – head uphill. A way-marked path leaves from Carrer de la Sagrera, climbs past vegetable plots and abandoned stone huts, then enters the oak woods of Sant Llorenç del Munt. After 45 minutes the track reaches la Roca del Vallès, a limestone bluff that overlooks the whole plain. From here you can see the coastal range, the glass towers of Barcelona, and the thin white line of the high-speed train snaking toward France. The round trip is 7 km; trainers are fine, but flip-flops will earn you a blister lecture from Catalan hikers.

Winter visitors should know the score: night frosts are rare but daytime highs can sit at 10 °C. The pools feel hotter when the air is cold, yet the old town shuts early. Restaurants lock doors at 16:30; miss lunch and you’ll be surviving on crisps until 20:00. Sunday is particularly strict – even the bakery closes.

Food that doesn’t rely on chips

Caldes has no sea, so fish arrives by truck and prices reflect the journey. Stick to the hinterland classics. Can Xarau on Plaça de la Font does a three-course menu del dia for €16: broad-bean stew in spring, wild-mushroom cannelloni in autumn, calçot onions grilled over vine shoots from February to March. They’ll bring bread without tomato if you ask; the waiters understand “plain” even when their English runs out.

For fussy offspring, Pasta Sanmartí hand-makes tagliatelle using thermal water – the gluten stretches silkier, or so the owner claims. Sauces are minimalist: butter and sage, or tomato so plain it could pass for Heinz. A child’s portion is €7 and arrives in under ten minutes, just fast enough to prevent a hunger-induced meltdown.

When the town lets its hair down

The main festival, Festa Major, lands on the first weekend of September. Saturday night is the Escaldarium: locals dressed as devils sprint through the streets swinging firepots, while drummers pound out a rhythm that rattles windowpanes. The route ends at the lion fountain where, at midnight, the mayor turns on an extra jet so the water arcs higher and the steam glows red. It’s spectacular, crowded and faintly dangerous – sparklers plus 74-degree water equals blisters. If you prefer quiet, come instead for the January bread festival, when the medieval oven is fired up and children bake rolls stamped with their initials.

Getting here, getting out

There is no railway. From Barcelona take the Sagalés 300 bus from Passeig de Sant Joan; the journey is 45 minutes if traffic behaves, €3.20 each way and contactless cards work. Buses leave every 30 minutes at peak times, hourly after 15:00. Driving is quicker – C-17 motorway, exit 12 – but park in the free Parc Can Rius lot rather than chancing the one-way lanes around the old baths. If you land at Barcelona-El Prat, allow two hours door-to-door: airport train to Sants, metro to Arc de Triomf, then the bus.

A half-day is enough to see the baths, dip in a pool and eat a decent lunch. Stay overnight only if you crave silence; the town’s two hotels are comfortable but nightlife stops at the ice-cream kiosk. Check out by 11:00 and the lion will still be spitting, the steam still rising, the queue of jerry-cans still moving – a reminder that some Roman habits refuse to die, even thirty kilometres from the Ramblas.