Square deal: The distinctive clock tower of Varazdin Town Hall on King Tomislav Square

The northern Croatian town opens its annual music and theatre festival this week. Mick Webb paid a preliminary visit

Asking citizens of European capitals where they go for a day out is always instructive. In Zagreb, I found a surprising number favoured Varazdin, tucked away in the north of Croatia, 90 minutes from the capital. The reason was consistent: the architecture. And they all used the same label, "little Vienna", because of the quality of its buildings. So I went to see the beautiful and unspoilt baroque centre for myself.

For 20 years in the 18th century, Varazdin was itself the capital of the country, until in 1776 a disastrous fire put paid to its short period in the sun. The fire, which destroyed half the buildings, was supposed to have been started by a young farm worker who was being chased by a pig while he was smoking a pipe, which he then dropped in some straw. The rest was history, or maybe just a good tale.

The journey from Zagreb takes almost two hours as the bus meanders through some gentle, wooded hills before gathering speed across the endless flatness of the Pannonian plain, which stretches to the Hungarian border and beyond.

Varazdin's suburbs turn out to be less off-putting than many of those built during the Tito era in the former Yugoslavia: the residential blocks are lower rise and the concrete has been softened with paint. The dominant building was a huge textile factory, Varteks. But a five-minute walk from the bus station, I found myself in Trg Slobode, "Freedom Square", and in a very different world.

It was a lovely, summer, Sunday morning and people of all ages were chatting in a relaxed fashion outside the church of Saint Nicholas, getting ready for 10 o'clock Mass. Those who weren't doing their religious duty were drinking coffee, as I discovered when I arrived in the central square of Kralja Tomislava.

Clearly the thing to do was to join them and drink in the surroundings. I chose a café terrace, one of four on offer, and sat down. Cyclists were the only traffic across the mosaic paving stones.

The square, which from next weekend will be one of the venues for the annual Spancirfest arts festival, was surrounded by elegant 18th-century mansions – mostly three storeys, with their stucco façades painted in a symphony of restful colours, ranging from ochre to pale pink.

Directly opposite my table was Draskovic Palace – a coffee- and cream-coloured confection from the second half of the 18th century; a discreet plaque attested to the fact that the Croatian viceroy, Franjo Nadasdy, lived here from 1756 and made it the capital until the 1776 fire. Unfortunately it wasn't open to the public, nor was there any mention of the beautiful Suzana Draskovic, who according to one rumour was the reason that Nadasdy moved his court from Zagreb, in order to be near her. A more likely reason is Varazdin's proximity to Hungary, which nominally controlled Croatia at that time.

Undismayed, I set out for the monument which gains most stars in the guidebooks: Varazdin's castle. But I was delayed on the way by an unusual museum – the entomological collection of Franjo Koscec, a local school teacher with a fascination for the natural world. The meticulously mounted insects weren't labelled in English, but that wasn't a problem with the interactive bird recordings: you choose a bird from its picture, press a button and hear its song. I tried some Croatian birds such as the Scops owl, which makes an eerie bleeping sound, before finishing with one I'd seen in my own London garden a few days previously: a goldfinch.

The castle exceeded expectations. Rather than a grey rectangular stone arrangement, it was a whitewashed fairy-tale one with towers, topped with conical red-tiled roofs. Its origins are medieval rather than baroque, and the interior, a labyrinth of corridors, halls and fortifications, is now a museum. There was an incredible variety of things to look at, many of which did have the benefit of English descriptions.

Some were genuine treasures: a ceremonial medieval silver mace, others beautiful, such as the huge and shapely 18th-century ceramic stoves, and some had a genuinely real-life feel to them, such as the collection of targets which had been given as prizes to the winners of archery competitions. They were beautifully painted with hunting scenes and evocatively punctured with arrow holes.

Varazdin's tourist office is closed on Sundays, but the receptionist at the castle-museum filled the gap. "Have you been to the cemetery?" she asked, unexpectedly. "You really should go."

So, as bells rang out from Varazdin's five churches, I set off for the well-signed Groblje which is another of the town's unexpected treats. Herman Haller, who was in charge of the cemetery in the first half of the 20th century, had a vision. He wanted to banish the "lugubriousness and sadness" associated with graveyards and create an uplifting "park of the living" which people would visit for its own sake. It had lines of tall hedges, trees, open grassy spaces, like a park or a very quiet campsite.

Birds flew and sang. I felt uplifted, particularly when I recognised one of the calls. It was a goldfinch.

When Spancirfest kicks off, the birdsong will be drowned by the sounds of buskers and street performers from all over Europe, while on the main stage the highlight will be the raucous excitement generated by the Celtic punk band Flogging Molly. For the rest of the year, Varazdin will return to its understated self – not exactly a Vienna, but an pretty place to spend a relaxing weekend.

Travel essentials

Getting there

Zagreb is served by easyJet (0843 104 5000; easyjet.com) and Wizz Air (0906 959 0002; wizzair.com). Buses run hourly to Varazdin from Zagreb’s main bus station (00 385 160 08645; akz.hr). A day return with Croatiabus costs 100 kuna (£12).

Staying there

There are no hotels inside the old centre, but the family-run Pansion Maltar at Franca Preserna 1 (00 385 42 311 100; maltar.hr) is a five-minute walk from both the bus station and the central square. Doubles with breakfast from €65 (£51).

More information

Varazdin’s Tourist Office is at Ivana Padvoca 3 (00 385 42 210 987; tourism-varazdin.hr). Its website has information about the town’s museums and castle. Spancirfest starts on Friday, 24 Aug and runs until 2 Sept: spancirfest.com.