#xanthi

This with a drink and good company.

The easy answer would be that Greek places can't look gloomy even if they try. I read an article some time ago which was discussing the reasons behind the limited production Greece has in dark atmospheric dramas and supernatural horror movies and the journalist added amongst them the unexpected yet valid point that "after all it's a little hard to create a dark, gloomy atmosphere in a country where you are constantly blinded by the sun" and it had impressed me because I had never thought of it this way.

A more thoughtful answer however needs to be more nuanced. By the way, I am also not perfectly clear on how to approach this topic because I haven't been to any of the city examples you provided but judging from photos none of them seems gloomy / shady / creepy to me, so I don't know if I am getting the exact feel you are looking for 100% . Personally I would reserve such characterisations for cities like London and Edinburgh instead, even New York, and also for Eastern European cities with Soviet legacy. To me, Prague also can look a bit eerie / creepy in the appropriate weather.

Which brings me to my original point, I think a great part of the impression places leave us have a lot to do with the climate conditions in the area. Architecture itself is just one part of it. This also works in reverse - the climatic conditions people are used to affect the architectural styles they come up with. Because you can take a fantastic black Gothic giant palace or something and put it next to a sun-roasted beach in the 40 degrees that Greece has today and it will look so out of place it won’t be impressive at all (disclaimer: gothic architecture is a fave of mine and I find it very impressive, my point is how weather conditions and the surrounding environment affects our perception of things). So, with this in mind, if I cheat a little and get help from suitable weather (winter, cloudy sky, fog) I think there are some places in Greece, especially the northwest, that could perhaps give a somewhat eerie vibe. Also, I think that I have seen many smaller towns and villages especially from Thessaly and Epirus and farther north that have such vibes but I will mostly mention some cities because it is too hard to search for villages that might fit the criteria.

Flórina

Florina in the northwest of Macedonia is the coldest overall regional capital city in Greece. Its architecture, its river, the often cold and gloomy weather give it an eerie atmosphere. I was there once and, unsurprisingly, it was cold and rainy. I loved it. Florina has also been the setting for movies of Theo Angelopoulos, who loved those gloomy vibes in his movies.

Creator: Konstantinos K 

Kastoriá

One of my favourite cities in Greece, very close to Florina. With its traditional architecture, the lake surrounding it from all sides, the very low temperatures in the winter and the frequent fog covering it in the early hours, it can have an otherwordly feel.

Xanthi

Going towards the northeast, in Thrace, the Old Town of Xanthi can have some beautiful shady - creepy vibes, especially if aided by the weather.

Kalambaka and Kastraki

Moving a little more south now, in Trikala, Thessaly, I would say that all of the unfortunately very few times I have been to Kalambaka I have been mystified. Technically, this is not the town's doing which is pretty standard looking (btw this is not the capital city of the regional unit - the capital is the namesake Trikala town), it's the effect the Meteora have on the town. The Meteora are visible from anywhere in Kalambaka and the nearby village of Kastraki and they can't not look mysterious or even spooky - in any case, extremely imposing - even in the brightest of weathers. But I have been there in cloudy weather and the feeling is unbeatable. They also get a lot of fog pretty often.

Ámfissa

Further to the south, in the Phocis region of Sterea Hellas (or Central Greece or Rumeli) being there in winter weather, especially during carnival season, when they have some apotropaic traditions with the Beast / Ghost of Hármena, can be legitimately spooky, but the preserved traditional district of Harmena in the upper town with the old tanneries is creepy on its own right. More points added by the fact that the town is built amidst the mountains and has ruins of an ancient acropolis and castle / fortress on top. A lot of beautiful mansions downtown, also, that can add to the feel in the appropriate weather.

Monemvasiá

Ending with the southmost edge of the mainland, in Laconia, Peloponnese, this might seem an odd choice but I have seen some photos of the castle city of Monemvasia taken at night and I thought it looked very mysterious and atmospherical. Moon is enhanced in these pictures but still...

Travel Greece 04 / İskeçe / Xanthi:

Yunanistan'ın Batı Trakya bölgesinde İskeçe ilinin merkezidir. Lozan Antlaşmasının imzalamasıyla nüfus mübadelesinden İskeçe Türk halkı muaf tutulur. Türklerin yoğun yaşadığı yerlerdendir. Yaz kış turistlerin ilgisinde, Avrupa Birliği tarafından Yunanistan'ın en iyi korunmuş eski şehri unvanına sahiptir. "İskeçe Eski Kasaba Festivali" bölgede ilgi çeken önemli festivallerdendir.