This was serious stuff. The doorman was dressed in full military garb, wielding a very real-looking PPSh-41 sub-machine gun and smoking a chunky cigar of 1980s action movie proportions.
"Slava Ukraini!" ("Glory to Ukraine!"), he barked at us.
Luckily I was with two cute Ukrainian girls who knew how to respond. "Geroyam slav!" ("And to its heroes!"), they giggled.
The man gave the slightest of nods. "Rosiyu?" ("Russian?") he barked again, pointing accusingly at each of us. "Nye." ("No.")
The man grinned and ushered us in to the bar.
It was a dramatic start to my first night out in Lviv. But then this is a city which just keeps on surprising.
At 5.30am that same morning - 10 hours after boarding the Kiev to Lviv (pronounced Liveev) overnight express - the lights flickered on and awoke me and my third-class sleeper carriage comrades from a surprisingly comfortable sleep.
Half an hour later, the train lurched to a stop in Ukraine's cultural capital and I got off on to the dimly lit platform at Lviv Central Station. At 6am, the temperature was about -15C which, compared with the chill of a few nights earlier, felt positively balmy. Not that anything less should be expected east of Eastern Europe in mid-winter.
While the cold was definitely refreshing, a shower and change of thermals was an imminent priority. Outside, cabbies were lined up, all smoking heavily in front of beaten-down Soviet-era Volga taxis and wearing world-weary expressions.
After clumsily negotiating an exorbitant 45 hyrvinia fare (about $7 - locals would pay a third of this), it was a 15-minute cab ride to my hostel, the Kosmonaut, on the southern edge of Lviv's old town.
This was a city vastly different from Kiev. The Ukrainian capital, along with most of the former Soviet Union, was devastated during the Great Patriotic War of 1941-45 and rebuilt with imposing Stalinist monoliths (nothing against Kiev - I loved it).
Lviv was one of the few cities that escaped such destruction and successfully retained its traditional Central European style. Even before I'd reached the town centre, I could see plenty of buildings that were an eclectic mix of Gothic, Romanesque, Baroque and Italian Renaissance, a world away from what I'd expected.
Let me paint you a picture. Take the glorious tourist traps of Central Europe - Krakow, Budapest, Prague, Vienna - remove tourists, and go back 25 years. Now you're in Lviv. The outstandingly beautiful architecture just has a slightly grittier, authentic feel to it. The cobbled roads serve droves of elsewhere-impossibly-elusive Soviet Volga and Moskvich avtomobil from the 1960s and 70s.
Even the prices are from another era, I thought as I handed over the equivalent of 8c for a cup of smouldering mulled wine.
The best place to take it all in at once is from Lviv Castle hill. While the castle has been gone for centuries, the panoramic views at the top are outstanding and really show off the city's best bits, in particular its glorious centrepieces, the Latin Cathedral and the Town Hall.
But getting in amongst it is what makes Lviv so much fun. It is wonderfully compact. Everywhere you turn there's another snugly hidden bar or cafe. Both of which this city does awesomely. Some even call it Little Vienna.
On a recommendation from Lonely Planet, I eventually found the underground coffee and hot chocolate joint known as Zolotyy Dukat, which was so good I almost lost all inclination to try anywhere else.
The huge menu (available in English) offers some of the most elaborately garnished coffee and hot chocolate creations anywhere ... ever. For just $1, I ordered a hot chocolate and was presented with a piece of culinary art that tasted like heaven.
That night I went with two of the staff from our near-empty hostel to Kryjivka (the place I mentioned at the outset). The girls took great delight in ordering a bottle of horseradish vodka and forcing most of it into me. The results were predictable. By the time food came along, I was well sloshed.
I vaguely recall eating a 1.5m sausage with some sort of mustard on the side. The girls dared me to try it. Feeling like Superman, I agreed, lathered on a ridiculous amount and bit into it. It tasted like molten lava and I spat it out. My eyes then welled up so badly that my contact lenses slid out and I gulped back two litres of water to banish the taste.
This was accompanied by riotous, knee-slapping laughter from every Lvivite within 10m. Still, it was an incredibly fun night.
This glorious secret won't be kept long. Next year Ukraine and Poland will co-host the European Football Championship, with one of the semifinals scheduled for Lviv.
It's already touted as a Prague-in-waiting and one can easily see why. Beautiful, affordable and well-hidden European cities are harder and harder to come by. My advice is to go there now.
Getting there: From Auckland, fly with Air New Zealand to London or Singapore Airlines to Frankfurt. The budget airline Wizzair flies to Lviv from London. Lutfthansa flies to Lviv from Frankfurt and a dozen other European cities.
Further information: Check out inyourpocket.com for good accommodation, bars and places to eat.
Michael McKerrow paid his own way to Lviv.