“Croatia's coastline may now be getting all the attention, but glance at a map of the country and you will see that it is shaped like a boomerang, with one blade pointing down the coast towards Dubrovnik and the other poking inland across the Pannonian plain. Few of us ever make it beyond the capital, Zagreb, so on a recent visit, I decided to explore the vast hinterland to the east.

This is a region bordered by Hungary, Bosnia and Serbia, where tourism has yet to make an impact, and where the emotional and physical scars left by the recent war are still clearly visible. And, unlike the chic coastal resorts of Istria and Dalmatia, it’s a place where they eat goulash rather than gnocchi, drink Turkish coffee rather than espresso, where few people understand English and you can still get a decent room for less than £20.

From Zagreb I headed north into the Zagorje region: all fairytale castles, green meadows and alpine villages. I spent the night in a cosy wooden farmhouse; my attic room had creaking floorboards, sloping ceilings and a picture of the Virgin Mary on the wall. Dinner was steak with wild mushrooms; breakfast was an omelette with home-made salami.

The main town of the Zagorje is Varazdin, so pretty that it reminded me of one of those lurid ice-cream sundaes that the Croatians love so much, all pastel-coloured façades in apricot, peach and vanilla, adorned with Baroque angels and garlands of flowers. Students swarmed around on bicycles and musicians were playing in the cobbled streets.

A long main road threaded eastwards across the plain. In small country villages, people sat outside their houses selling sacks of potatoes and peppers to passing motorists. My first stop was Hlebine, a village which became known in the 1930s as the birthplace of naïve art, when a local farmer, Ivan Generalic, began painting pictures of rural life on glass.His son, Josep, lives in the village and has his own gallery.

Reality of a different kind caught up with me in Osijek, the capital of the eastern province of Slavonia. Skateboarders and joggers on the riverbank gave the place a relaxed, easygoing feel, until I found myself at the centre of the 18th-century fortress and noticed the pockmarked façades of the buildings.

The town was repeatedly shelled during the war with Serbia in the early 1990s. I retreated inside a folksy little tavern for a plate of spicy Slavonian sausage and a bowl of fiery fis paprikas (fish stew).

“Will you be going to Vukovar?” asked Renata the next day, after my boat trip in the Kopacki Rit, part of the Danube flood plain, where I had seen herons and cormorants among the marshes. Renata had grown up in Australia, but her family had returned to Croatia just before independence and had spent the war under siege in Osijek. Like other Croatians I met, she wanted me to see Vukovar because it has become a symbol of their suffering after the siege of 1991, when at least 2,000 people were killed.

It took less than an hour to drive there, across a flat and lonely landscape, passing abandoned vineyards and fields. The town was deserted, apart from a coachload of visitors from Zagreb who were paying their respects at the riverside memorial, within sight of Serbia on the far bank Along the Danube, in the border town of Ilok, I stumbled across a wine fair in celebration of the harvest. Dancers in folk costume gathered into circles to perform the kolo to the sound of the tamburica (Croatian mandolin). Children threw bunches of grapes in the air. During the war most of the locals fled, but the farmers have returned and Ilok is producing quality wines again.

My route back to Zagreb took me along the River Sava, which forms a natural border with Bosnia. As long ago as the 16th century, Pope Leo X referred to this border as “the ramparts of Christendom”, and it seems to have been fought over ever since.

I stopped for coffee in Slavonski Brod and wandered around the star-shaped fortress, built in the 18th century on the boundary of the Habsburg and Ottoman empires. During the recent war, the townspeople took refuge in the fortress as it was bombarded by Bosnian Serbs. Christian against Muslim, Catholic against Orthodox, Serb against Croat. In 500 years little had changed.

The Lonjsko Polje nature park occupies a large area of wetland on the flood plains of the Sava. Heavy Posavina horses graze on the summer pastures, while spotted Turopolje pigs root for acorns in the oak forests.

In the village of Muzilovcica, Miroslav and Zlata Ravlic have turned their 200-year-old oak cottage into a small guesthouse and restaurant, popular with day-trippers from Zagreb. Miroslav proudly showed me his photo album, with pictures of him and his family receiving awards for being pioneers in rural tourism.

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