How to Get Here
By Airplane
Makedonia Airport is about 15 km SE of the city center of Thessaloniki. Its IATA airport code is SKG, and its ICAO airport code is LGTS. It is the second most used airport in Greece. It has international flights to European and Middle Eastern cities.
The website of the airport is: www.thessalonikiairport.gr 
The call center of the airport can be reached at: +302310985000
Some of the airlines that fly to Thessaloniki are: Aegean Airlines, Air Berlin, Alitalia, Austrian Airlines, British Airways, Chezh Airlines, Easyjet, Germanwings, Malév Hungarian Airlines, Olympic Airlines, Sky Europe, Swiss International Air Lines and many more.
Alternatively you can fly to Athens and get a train to get to Thessaloniki.
Athens International Airport Website www.aia.gr
By Train
The Greek train company is called OSE and the website can be reached at: www.ose.gr
By nighttrain from Athens (Larissa station), about 6 h. Costs 20€-31€ (depending on the train), or about 50 € if you want a sleeping compartment to yourself.
Daily trains from Athens take 4h 15 min (intercity express trains), 6h(normal trains) cost about 50€ euros first class. A very good option are the 500/501/502/503 trains, delivering excellent quality of travel at a low price, costing about 14€ euros (11€ for students and people up to 26) and take only 5h 45min. The last train at night departs at around 01:50.
There is also a night train (sleeping car) from Istanbul, departure every day at 20.00. It arrives 08.00 next morning and costs 48€.
When you are under 26, you get a discount for 25 % on most trains.
To/From Skopje, - direct link: Skopje to Thessaloniki train is 20€ RT with young person discount, 20% more without. Train leaves from Thessaloniki at 8:00 a.m. Skopje to Thessaloniki train leaves at 4:15 p.m. Both trains take about 4 hours.
There are also direct train connections to Sofia (at 06:16 and 17:39, take 6 hours), Belgrade (12 hours), Istanbul (12 hours-every evening-arriving next morning), Budapest and Ljubljana (24 hours) via Zagreb (21 hours).
By Car
From Athens about 5 hours (Highway)
From Istanbul about 8 hours
From Belgrade about 7 hours