Massively ornate wrought iron gates leading to what? A grandly exclusive apartment block? The east European headquarters of some major international corporation?

We climbed the sweeping staircase up several floors, knocked on a discretely anonymous door entry to a haven of softly lit, velvet-and-lace fin de siècle hedonism, a home to clinking glasses and hushed tones.

This was no bordello but one of the best of Belgrade’s secret-rendezvous drinking clubs – a hangover from the Communist era, when fun had to be engaged with discretion (“Knock three times and ask for Ivan”).

This one’s called The World Travellers Club – a haven for journalists, writers, artists and politicians too – and it’s just one of many such rendezvous that are dotted across the Serbian capital.

Belgrade has many such secret delights it keeps close to its chest, making every visit a voyage of discovery even for those who may have been many times before.

Stand aside Amsterdam, Prague and Barcelona – this is Europe’s new capital of cool, with not only 42 museums, 67 art galleries and 26 theatres but a vibrant café society and lively nightlife, It’s a history packed but thoroughly modern city for the young and the young at heart.

Strung along the banks of the mighty Danube and its River Sava tributary are more than 150 floating restaurants, bars and clubs. Euro pop? Jazz funk? Hip-hop? Rap? Traditional Balkan folk music – you’ll find it all here. They even have turbo-folk!

There’s an infectious mood for having fun that dates back to the dark days of the break-up of Yugoslavia: “The West has bombed the hell out of us already and sooner or later they’ll be back to do it again. So, in the meantime, let’s eat drink and be merry, for tomorrow we die” was the maxim at the time,

Today, things are looking far more optimistic and, with living standards improving rapidly, fatalism has been replaced by impassioned hopes for a positive future.

People are well dressed, the shops are well stocked, public buildings have been spruced up and the infrastructure is of an appropriate standard for a modern European city of more than two million.

Downtown, with its department stores and boutiques, is bustling; the bohemian Skadarlia district has been compared to Montmartre, while Zemun, on the right bank of the Danube, is truly charming.

There are some fine hotels too, A short taxi ride – and those are cheap – took me from the centre to the very à la mode Hotel Zira (zirahotels.com) an intimate and welcoming boutique gem with all the latest amenities. Of equally high quality is the downtown Belgrade Art Hotel (belgradearthotel), a 55 rooms and suites Italian design influenced delight set on the main pedestrianised shopping street, where I stayed on my final night.

In between, I took a trip out into the lush countryside whose low mountains and red-roofed architecture reminded me of Burgundy – and, indeed, they produce some fine wines here.

The flavour of the little town of Urovica is definitely Romanian kitsch however.

Despite everything that’s happened, Serbia remains a multi-cultural country and has sizeable Hungarian and Romanian communities among its ethnic minorities.

The exuberant, well OTT architecture of Urovica – with everyone seeking to outdo the excess of his neighbour – is nothing short of quirky. I’ve never seen so many rampant lions and ornate plaster mouldings. One family even has a scale version of the Eiffel Tower dominating their lawn!

The broad Danube, with its huge commercial barges and floating gin palace hotel cruise ships, was crossed by an ancient ferryboat close by the entry point to the famed Iron Gate Gorge, where the mighty river narrows down to slice between towering mountains and provide a natural frontier between Serbia and its Romanian neighbour.

The imposing Golubac fortress, now a romantic nine towered ruin, could not have been more strategically well placed.

Close by, at Lepinski Vir, archaeologists are slowly unearthing a sizeable 8,000 year old village. Also well worth a visit is the formidably fortified Manasija monastery. Better still were the restored Rajac wine cellars, near Negotin – there are more than 270 of them – where what was billed as a light lunch turned out to be a succession of hearty traditional dishes – cured meats, cheeses, goulash, succulent lamb and more. Move aside Michelin, this is real food1

Great for hiking – and both road and mountain biking too – Serbia has a wealth of natural wonders.

You can explore deep inside the vast Resavska Cave, with its prehistoric decorations, and hike along vertiginous paths through the virginal woods to the spectacular Veliki Buk waterfall and Veliko Vrelo spring.

From big city Belgrade to remote villages where the horse and cart still has a role and from fertile plains to towering limestone crags, Serbia might be a small country but it has a kaleidoscopic appeal.

Belfast Telegraph