I've been 3 times in Thessaloniki, never with the solely intended purpose of visiting the city. And yet, when I look at all the cities I've visited, Thessaloniki is one of those I always recall first.
It's not easy to say what makes Thessaloniki such a lively, lovely city: if the activity of its city centre and Kamara or the attractive carelessness of its old town district; if the restaurants and bars by the seaside in sunny afternoons or the intense typical (I'll never come to terms with this word) Greek taverns at night.
It's probably also difficult to 'sell' Thessaloniki as a tourism destination: let's face it, looking at the map of the region, why would someone choose the city over the beautiful, clear water beaches of so many Greek Islands? If you're into ancient history, why not go to Athens instead? At least the Acropolis will surely give you decent photo-ops, something not as guaranteed by the few monuments Thessaloniki has. Despite being the second most important city in Greece, it has the same touristic potential as, say, Rennes or Parma.
And yet, I'd be happy to return to Thessaloniki at given time. Why?
1. The people. 'The people' has become the number 1 cliché to describe cities in Southern Europe. But maybe that's for a reason: people are welcoming, relaxed and you'll likely feel good among then.
2. The atmosphere. I'm sorry if I'm ticking all the clichés, but this one seems even truer to me than the other one: walking by the seaside while drinking a frappe (a real one, costing no more than 1 euro at many coffee shops all around the city). Walking with no particular route through the old town. Sitting in one of the thousand is cafés the city has, ranging from taverns to boutique bars and lounges. Trying souvlaki on one of the main squares. Going out to a Greek tavern until later than you would imagine – even on a week day. All that will make you look back to Thessaloniki with joy – you're bound to enjoy yourself there.
3. It's pretty and NOT tourist-packed. Because everyone is getting sunburnt in Mykonos or taking selfies at the Akropolis, Thessaloniki isn't so crowded with tourists – despite being served by many airlines, including Easyjet, Ryanair and Wizzair. That gives you more room to breathe, but also to explore the city at your own rhythm. The fact that Thessaloniki isn't as crowded as other places also makes locals less fed up with tourists and more willing to help you find your way wherever you're going.
4. There's a rich, busy cafe and restaurant culture you ought not to miss. The same applies to the nightlife. Ask around, you'll be surprised how many doors you'll be able to open (quite literally: there's bars that only who lives there knows they exist).
5. It's backpack-friendly. Needless to say, that means cheap. As in the rest of Greece, the maximum you'll pay for a bottle of water is 50 cents, which comes pretty useful when the heat kicks in. The hostels are by and large cheap, comfortable and clean. Eating out is pretty affordable and the same goes for drinks. You must try ouzo – it's pretty likely you'll regret it sooner or later, but you must at some point.
On a more personal note, the last two times I was in Thessaloniki, in December last year and this April, I found people I had met in other countries (that being two Ukrainians I had met in Kyiv and one Spanish I had met in Leiden) there, by complete accident. In one of the cases we ended up going out for lunch. Thessaloniki may not be a metropolis, but certainly knows how to play one from time to time.
P. S. – there's nothing wrong with Rennes or Parma. I spent nearly a week in the latter and loved it as well.