I discovered these bars gradually while living in the Dorćol district of old Belgrade (Serbia's “Manhattan”). So this article, which I've been sitting on until now, is a product of a time when I called this city home for a while. The establishments I've written about are barely advertised – usually discovered solely by word of mouth – and the very fact that they are essentially invisible entities lends a mythical quality to the Serbian capital. It was from a traveller I met in Hungary, for instance, that I first heard talk of a bar in an abandoned hospital in Belgrade. What's certain is that this is particularly hard to find – but in hushed secrets like this one, real or otherwise, rests the pure essence of Belgrade's nightlife... an essence that's ethereal, and far deeper-plunging than the pouty clubs and moored river boats that come to life in warmer months would have your impressions believe.

Here's a selection of seven genuinely hidden bars in central Belgrade – in unmarked basements, down cleaning corridors, behind garden gates, shed doors, and buried high in unassuming apartment buildings. All within a brisk walk of each other and full of personality, each in their own esoteric ways. Yet know that the nature of these establishments can be transitory – some closing abruptly then returning at an undisclosed time, others not lasting beyond a medium term. Some still exist and some have since closed (temporarily or otherwise)... though I like to think of them as still there, as they were when I wandered Belgrade's streetlit shadows.

Ilegala (Akademski plato 1)

Walk through the Plato bookshop and descend the discreet stairs in the corner that lead into the large basement. There you'll find the sprawling, dark, industrial décor and cheap draught beer that makes Ilegala special. Tables are laid out in front of the soundstage and up on the large metal frame gallery, with its chipboard floors and heavily graffitied mini palette tables. The seating consists of cushioned gas cannister stools and rice sack-covered benches. And the bookshop shielding this hideaway from above remains open until midnight.

Pubby's Magic Garden (Makedonska 5 at TC Staklenac)

Within a small shopping centre this cosy bar is hidden down what appears to be a dead-end corridor leading to a cleaner's cupboard. To get to the Magic Garden from Republic Square, head across the road, aiming for the subtle glass frontage of the TC Staklenac shopping centre. Enter left of the pizza place and follow the green corridor. At the end you may or may not need to push the wall, where an unexpected pleasure awaits through a little dark courtyard. The lightly Dada-inspired, almost decadent interior of the Magic Garden sets it apart as a fitting hangout for the artists of the city. A mustachioed Mona Lisa greets you on the drink menus.

Tijuana (Prizrenska 8)

A particular favourite among the foreign visitors fortunate enough to discover it. Find the door into the residential apartment block down the side of some steps that connect Sremska with Prizrenska. Climb the stairs inside the building to the second floor, and open the door on the left – no need to ring the doorbell (unless the door's locked). Light graffiti and a riot of colour covers most of the wall space of this energised apartment bar. Tijuana's wrought iron balcony gives something of a panorama over the thick atmosphere of Brankova – the busy traffic artery around which Belgrade's art district is forming. Finally there's a retro surprise in store in the unisex toilet, and I'm not referring to the chaise longue.

Rif Jazz Club (Makenzijeva bb)

A piano-at-the-ready jazz bar nestled among a collection of large shed-like constructions, slightly out of the very centre in nearby Vračar. At night, as you step onto the wooden porch, Rif's barred black windows and ramshackle look from outside make it appear disused. It's a pleasant surprise then when the door opens, letting you into a place that white light has forgotten. Inside it's filled with vintage curiosities of every texture imaginable – a straw hat hangs from a noose in a hole in the wall – and it's all bathed in a seductively low blue and yellow light that creates Rif's dark ambience. And, to the left of the red-lit fridge, there's a very cool toilet complete with thick curtain. Uncover Rif behind the Sava temple, where Makenzijeva meets Mačvanska, by weaving yourself through the cluster of brown wooden buildings.

Podmornica Rock & Roll Basement (Čavketov pasaž, off Nikola Pašić Square) 

Podmornica, meaning 'submarine', is one of the best hidden bars in Belgrade. If you're lucky you'll become acquainted with the owner and his super-sweet banana rakija. The little-known basement opens from 9pm to 2-3am, with open jam sessions on Thursdays, a DJ or band on Fridays and Saturdays, and regular photography exhibitions on quieter weekday nights. It's a no-nonsense bar and venue that's a favourite of Belgrade musicians and visual artists. Go down some discreet steps in an alley called the Čavketov pasaž and revel in Podmornica's cheap drinks, unique friendly atmosphere and mix of clientèle.... you'll be a stranger no more.

The World Travellers' Club aka The Federal Association of Globetrotters (Bulevar Despota Stefana, 7)

A speakeasy of 20 years ago, situated in an apartment in the basement of a residential building. This modern-historical “grandma's house” is perhaps the most widely known example of Belgrade's tradition of well-hidden bars. Awaiting the curious visitor is an otherworldly foliage-filled indoor garden with running water feature, while the walls of the main room are generously adorned with old photographs, books and masks. From the comfort of a vintage easy chair, the rich palette of an Aztec René Magritte can be imagined by marvelling at the colours on display here. Stone blue, tones of yellow, vintage green, copper, brown-oranges and a sumptuous red lamplight. It's reminiscent of the crystal maze; all that's missing is a Richard O'Brien substitute leaping around the place. Ring the doorbell for the basement if the door to the building isn't open; you'll be buzzed in.

Dvorištance (Braće Krsmanović 14)

Dvorištance is a well-concealed spot that's full of beach bar charm, tucked away in an industrial-looking corner of Belgrade's growing creative district – a collection of streets where old buildings are gradually being transformed into hubs that fuse art with nightlife. Past the shadows of Brankov bridge, let yourself through an unmarked tall garden gate at a dead-end surrounded by the small factories and workshops of old Belgrade's riverbank. Turn up here late for informal table service, eclectic music, and an illuminated view over the Sava river towards New Belgrade. Dvorištance really does capture the character of the Serbian capital. It's magical.

Raring to go?

There are plenty of secluded places to explore in Belgrade's tangible underground bars. And there are more hidden spots further from the centre that also keep a low profile. These seven are a taster – a saccharine hit for the imagination. But what of the abandoned hospital drinking spot? Well it still confidently remains a mystery; but from the story that was relayed to me, it's in the last room at the end of a long, dark, isolated corridor with high ceilings... And inside that room I pictured a wood-panelled operating table forming the makeshift bar, small fridges behind it filled with half-litre beer bottles, white cabinets in the corner, rotting windows looking down onto a dark courtyard, friendly people enjoying their improvised discovery together. The mythical essentials are all there. Belgrade is the forerunner for the clandestine beer, if you make time to find one.

(Wizz Air run direct budget flights from London Luton to Belgrade – www.wizzair.com)