Clanking cowbells filled the air as about two dozen zvončari paraded through the village of Rukavac, just west of Rijeka. To me, they looked like pagans from a Grimm’s fairytale: shaggy woolly gilets, those bells hanging round their waists, and heads adorned with towering flower-covered hats. Exaggerating their gait to make the bells jangle, they shimmied and bumped their hips against each other as they waved carved wooden figures with a somewhat menacing air. Over the course of a 25km procession, they were here to banish evil spirts and herald the coming of spring. Carnival had come to town.

Villagers around Rijeka, Croatia’s largest port, feel pride towards their zvončari, who have been carrying on this tradition for several hundred years. They are also quick to point out that their bellringers, not the ones at Rijeka carnival, are the originals. However, most people still associate zvončari with the country’s biggest carnival, which this year has been bubbling along since late January and will end with a parade on 23 February. This will be when thousands of masked participants in elaborate costumes, pass along Rijeka’s main pedestrianised street, Korzo, joined by floats poking fun at political and celebrity targets.

Facebook Twitter Pinterest Zvončari in Rukavac. Photograph: Adam Batterbee

In 2020, though, the carnival has a rival for attention, because Rijeka (along with Galway) is European Capital of Culture. The main programme kicked off on 1 February with a lavish waterfront ceremony focusing on the city’s past as an industrial powerhouse – that at times sounded like the love child of German heavy metallers Rammstein and Einstürzende Neubauten having a tantrum. “Shocking and provocative, that’s what Rijeka does best,” a friend, who loved the show, told me afterwards. “Horrible – too industrial and noisy,” said another. While the ceremony divided opinion, the appearance of 400 zvončari united all in the crowd, as did the spectacular fireworks.

What also hit the right note, despite the rain, was the party atmosphere throughout the city centre. I walked past dozens of live performances: rock, jazz, classical. Stages had been set up in squares, on quaysides, in a tunnel, even in the temple-like indoor fish market. It gave me a taste of what’s to come this year, with literary festivals (including one celebrating the short story, in collaboration with Hay Festival), indoor and outdoor art installations and exhibitions, rock and classical music concerts, and an opera and theatre programme at the city’s Italian-style Croatian National Theatre.

Facebook Twitter Pinterest Fireworks during the opening ceremony of Rijeka as the European Capital of Culture 2020. Photograph: Antonio Bat/EPA

Many visitors overlook Rijeka in their rush to reach islands in the Kvarner Gulf – Krk, Cres, Rab, Lošinj – or neighbouring Istria. But multicultural Rijeka has a way of beguiling with its Habsburg architecture and legacy of being part of the Austrian empire. Italy once ruled here too, leaving behind traces in cuisine, architecture and dialect. The Maritime and History Museum of the Croatian Littoral is a former governor’s palace designed by the same architect who created Budapest’s ornate parliament building. It was a good place to try to get a handle on Rijeka’s centuries of complex history. Also, it’s not often you’ll get to look at a lifejacket worn by a Titanic survivor – especially for an entrance fee of just 30 kuna (£3.35).

A few minutes from here, Peek&Poke is a geek’s heaven of I vintage technology and gadgets in an endearingly quirky and overstuffed museum. Next, I crossed the Rječina River towards a stone staircase leading up to one of the city’s most picturesque viewpoints. Trsat Castle, which dates from the 13th century, offers grand views over Rijeka and the Kvarner Gulf. It’s free to wander round the castle’s tower and grounds, and it’s only a few minutes’ walk on to the vast gardens surrounding Trsat’s Franciscan monastery.

Facebook Twitter Pinterest Rijeka’s indoor fish market. Photograph: Adam Batterbee

Korzo is the city’s hub, with cafes that spread along the marble street while graceful Habsburg palaces (and the odd Tito-era addition) tower above. Narrow side streets lead to squares with more cafes and shops, the rotunda-shaped St Vitus Cathedral and even some Roman ruins. The large glass-covered terrace of Konoba Primorska offers a taste of the region’s gastronomic mishmash: squid-ink risotto, sauerkraut and sausages, grilled sardines with chard and potatoes, and at prices lower than elsewhere on the Adriatic coast (dishes from £3.35).

The Riva waterfront promenade attracts strolling crowds, as does the Molo Longo concrete pier, but while there are pebbly and concrete beaches near Rijeka’s port, many prefer to take a 30-minute bus ride west to the Opatija Riviera. I took one look at Opatija’s wedding cake-like 19th-century villas and hotels and saw why this was the best place for a seaside fix. The Habsburgs turned this elegant, laid-back place into their own riviera during the mild winter months, a process chronicled at the Croatian Museum of Tourism in the town’s landscaped gardens.

Facebook Twitter Pinterest Volosko, near Opatija, Croatia. Photograph: Adam Batterbee

I finished by following the 12km Lungomare (the Capital of Culture celebrations include an art trail along it) that hugs the coast from pretty Lovran past Opatija and to the fishing village of Volosko. It’s easily one of the most pleasurable walks along the Adriatic coast. Both Lovran and Opatija are sharing Rijeka’s reign as culture capital, along with 25 other neighbourhoods. It’s going to be one hell of a party.

• The trip was provided by the Croatian National Tourist Board, with accommodation at Rijeka’s Hotel Continental (doubles from £76 B&B) and Hotel Ambasador in Opatija (doubles from £75 B&B). Details of rail travel to Rijeka at hzpp.hr and of coach/bus travel from European stations at arriva.com and Flixbus For more information see visitrijeka.eu, kvarner.hr and croatia.hr

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