The bus leaves Monday to Friday at 8.30am sharp outside the Sant Antoni market in Barcelona’s Eixample district, but this is no ordinary vehicle; it has hundreds of wheels, dozens of drivers – and no passengers. This is the Barcelona bicibús, the fun, safe mode of transport that makes going to school feel like a party.

On a cool September morning, a group of about 60 parents and children aged three to 11, on bikes and scooters, gather in the Plaça Conxita Pérez for the school run. This being Friday, the mood is especially festive. Dua Lipa’s Dance the Night is playing and there’s an air of excitement as though the kids were going on an excursion, not just to school.

“When we started out two years ago there were 20-30 people, now there are 60-70,” says Genís Domínguez, a bicibús organiser. The concept has been around since the 1990s, he explains, but locally, it began three years ago in the Catalan town of Vic.

However, he says, they’ve had to adapt the idea for it to function in their neighbourhood. The Eixample (meaning the extension) is a grid system of streets that more than doubled the size of Barcelona at the end of the 19th century. Designed around what were then radical concepts of public health, the streets were wide to offer citizens breathing space compared to the confines of the densely populated old town. But today these same streets are choked with traffic.

Whereas in Vic the bicibús follows narrow streets or cycle lanes, the only way to move safely in the Eixample, with its high volume of fast-moving traffic, is to occupy the entire road, and to treat the bicibús as a single vehicle. One or two adults lead the group, with two or three others on each flank. A police patrol car brings up the rear to ward off any impatient motorists.

“The police sent lots of units to begin with,” Domínguez’s colleague Mireia Boix explains. “In front, behind, at the sides. We didn’t want two patrol cars and two motorbikes. We talked to them, always trying to find common ground, and settled on a single patrol car at the rear.”

At each cross street the adult riders on the flanks block the traffic to let any stragglers cross and to stop anyone jumping the lights. Aside from the police car, the entire operation is run by parents via a WhatsApp group. It’s lively but surprisingly orderly and there’s little or no conflict with motorists.

It’s also clearly a high point in the children’s day. “What I like best is chatting to my friends while we’re on our bikes,” says Alex Hurtado, 9. “For me the best thing is we can put on music and we get to choose which songs we want,” says Rita Camprubí, 7. “What I like best about the bicibús is meeting girls and boys I don’t know from other schools,” says her four-year-old sister Lola. Jana Camprubí, 4, adds: “What I like most is to ride at the front, like I’m the driver.”

There are now about 15 bicibús routes in the city, operating two or three days a week. (As most children have extracurricular activities such as sport or music classes after school, and don’t all finish at the same time, there is no BiciBus for the homeward journey.) The Sant Antoni route is especially popular because most of the children have to cross one six-lane and two four-lane streets to get to school. The alternative is public transport or to go on foot. Few parents drive their children to school in Barcelona. The Barcelona BiciBus Network estimates that around 15,000 bicibús journeys were made during the previous school year.

The scheme is attracting attention and imitators in Spain and beyond. Boix says they have had inquiries and visitors from France, Italy, the UK and Germany. “It’s an easy model to replicate elsewhere,” she says.

School teachers claim that children arrive more refreshed and alert when they use the bicibús, although one issue is that city schools have little space to store bicycles. Most of the children on the Sant Antoni route go to Xirinacs and Entença schools, next door to the former La Model prison, which has given them space to park their bikes.

Domínguez says they have asked the city council to provide secure bicycle parking, and adds that bicibús is part of a broader campaign to make the city more child-friendly. “From the start, our message to the city council was that children can’t cycle safely in the city, which is part of a wider discourse about how the city isn’t geared towards children and their safety,” he says.

To this end the bicibús network has presented a series of proposals to the city council to make the roads safer for children. These include more cycle lanes (the network of bike lanes has grown from 120km to 275km over the past 10 years), a maximum speed limit of 30km/h, promotion of new bicibús routes and extra measures to protect young cyclists, such as allowing 12-16 year-olds to ride on the pavement.

Riding in the car-dominated Eixample in a group of dozens of small children is not only fun, it feels empowering, a sense of reclaiming and humanising the streets, if only for 20 minutes. Everyone involved agrees that, as well as providing a safe and healthy journey to school, bicibús increases a sense of community and also means children from different schools (there are three on the Sant Antoni route) get to know each other.

“In a neighbourhood such as the Eixample, it’s often difficult to feel integrated,” says Rosa Suriñach, a social policy adviser riding with three little girls packed into a cargo bike. “Bicibús helps to create a sense of belonging.”

Anyone interested in establishing bicibús in their own town or city can find useful advice on how to establish routes, manage participants and monitor the impact of the project at bicibús.eu. or at bicibus.cat, the latter only available in Catalan