"Here?" asks the taxi driver. "I think so," I reply, tentatively.
I can feel him watching me as I cross the street and approach the anonymous-looking building. There is no sign, no smiling concierge, just a sleek metal door and an electronic key safe. I furtively glance left and right before punching in my code, retrieving my key and silently letting myself in.
I imagine him driving off convinced he's just delivered a spy to a Viennese safe house.
Sadly, I don't work for MI6 and this isn't a safe house. It's an Urbanauts "loft" and it's the brainchild of three young Viennese architects who have been quietly transforming disused shops and galleries in Vienna's fourth district into funky, self-contained hotel rooms.
I'm staying in The Tailoress, which in a previous life was the workshop for haute couture dressmaker Liane Lerner. For more than 50 years she used this space to produce extravagant evening gowns for Vienna's ball season.
Cleverly, the interior design of each loft reflects its former use. Splashed across the entire back wall of my room is a backlit photo of a woman in a ball gown teasing wool from a sewing machine. Instead of a cupboard, I have a sumptuously upholstered hanging area.
At 25 square metres, the room is larger than a standard hotel room and has a spacious walk-in shower and separate toilet. There are some nice touches such as a welcome note tucked into a vintage typewriter and a mini-bar stocked with complimentary snacks, juices and miniature bottles of spirits.
There's also a coffee machine, free Wi-Fi and an Apple Mac for internet browsing or watching DVDs (an appropriately arty selection is supplied).
The setup isn't entirely glitch-free: the Wi-Fi is sluggish and there's not much storage space but these are minor niggles. Overall, I feel like I'm staying in the apartment of the stylish Viennese friend I wish I knew.
The loft's location is deceptive. Step outside and you could be in any of Vienna's well-heeled suburbs. Opposite is an exclusive school for diplomats; down the road are the Romanian and Vatican embassies.
It's only when I hop on a tram and emerge five minutes later in the city centre that I realise how close everything is. To walk home from St. Stephen's Cathedral in the heart of the historic district takes me 25 minutes.
While the loft is well-provisioned, a man can't live on coffee and miniature bottles of gin alone. To compensate for the lack of big hotel facilities, each loft contains a map highlighting a selection of "fellows" – complementary businesses that the Urbanauts team know and recommend.
So rather than trying somewhere random for breakfast, you can go around the corner to Cafe Goldegg safe in the knowledge you'll be experiencing a traditional Viennese coffee house that is recommended by locals (see sidebar for more).
All in all, it's an inspired concept and all the more impressive given it's happening in Vienna, a city known more for tradition than innovation. At the time of writing there are five lofts in operation but the plan was to have 10 by the end of 2014. In the words of co-founder Christian Knapp, the aim is "to create a boutique hotel spread horizontally across the neighbourhood". What a good idea.
Five more Urbanauts lofts and initiatives
Formerly the gallery and exhibition space of curator and international art critic Ernst Hilger, this is now a stylish 35-square-metre loft with separate bathroom, Argentinierstrasse 55.
Located next door to the Gallerist, this loft is where Hilger's artists in residence used to work, creating paintings that have since been snapped up by Roberto Cavalli and Leonardo DiCaprio, Argentinierstrasse 55.
This 25-square-metre loft was once a traditional forge that helped manufacture the magnificent wrought iron gates of the nearby Belvedere baroque palace, Belvederegasse 26.
Formerly a "trafik" – a small store selling cigarettes, stamps and bus tickets – this space has been turned into a stylish 25-square-metre loft with a king size bed, rain shower and the use of two bikes, Belvederegasse 22.
Last year Urbanauts established a 500-square-metre pop-up loft in a concert hall in the Ottakringer Brewery. The next pop-up will be in a school classroom.
Qantas flies to Vienna via Dubai. Phone 13 13 13, qantas.com.au.
A night in The Tailoress (Theresianumgasse 35, 1040 Vienna), The Blacksmith (Belvederegasse 26) or The Tobacconist (Belvederegasse 22) costs $175 per night. A night in The Gallerist or Artist (Argentinierstrasse 55) costs $205 per night; see urbanauts.at/en/.
The writer was a guest of Urbanauts.