And Peter has replied:

We were there from 6-June until 8th of July 2018. I think safety is not an issue, 24 hours marinero duty. Port police are at the entrance. Cars need a chip for entrance. Sufficient lights at night. I would not winter there as it is too cold for me.

Snow is possible and temps below zero also for a few days. The nearby city Sub Kalamaria has several supermarkets and a cost center square. Nautilus chandlery nearby 400 meters another one at 3 km “marinas store” (lalizas)

Pleasant, friendly ladies in the administration office. Bus to Thessaloniki center 1 Euro single way. Many people leave their boat there in summer for a few weeks to return to their home country, as the airport is only 8 km away (14 euros taxi).

I never had an unsafe feeling there, but …it was summertime!
50ft is not a problem, it’s a large harbor. They can lift boats with a mobile crane, however no shipyard.

Hope this helps.

We were in Thessaloniki in June 2018, it is a perfect harbor to leave the yacht unattended. Double mooring-lines and no swell. Port police have an office in the harbor. Drinking water is included in the harbor fee, electricity 1 Euro every day for the connection and 15 cts per Kilowatt.

At the coastal road, one will find bus number 5 that will bring you to the center of Thessaloniki for 1 Euro one way, about 3 or 4 times/hour. Many restaurants at the coastal road and also in the harbor area. We did not find a chandlery at the harbor but there is one “Nautilus” at 200 meters from the entrance.

Diesel per Tanker and to avoid fraud you have to order the number of liters before they come. They prepare the bill in the diesel company office. In summer enough space, but it is recommended to call in advance. Mostly there is a big Motor-yacht moored at the central jetty so call them when you are near the entrance of the harbor.

When we were there we had a lot of (aggressive) mosquitoes. Post office is at 850 meters, several atm´s and supermarkets also at that distance.

They have a very funny / mystique way of calculating the harbor fee´s a month is parallel to a calender’s month. Shorter than 20 day´s means 50% extra. So best is to arrive the first of the month when you are planning to stay longer than a few days.

Many people come here and leave their yacht for a couple of weeks/month´s and fly home, the airport is at 8 km, taxi is 13 €uros. Rental cars at the airport or in the area close by. Kalamaria is the name of this part of the city