The 2nd largest city in Greece, Thessaloniki, is home to about a million Greeks. It is also home to over 3,000 years of colorful history and is a great destination to visit for travelers interested in history and culture. The Byzantine churches of Thessaloniki are part of the UNESCO World Heritage list.
There are many ways to reach Thessaloniki. Most people arrive by train, there are plenty of services running each day to and from many major cities in the country. There is also an airport, though it is a bit far away from the city central (about 15 kilometers). Many bus operators also run services to Thessaloniki. Getting around inside the city proper once you're in a Thessaloniki hostel is generally done best by bus. If you want to catch a sightseeing route, grab the bus #50, which runs close to most of the major tourist attractions.
Hostels in Thessaloniki vary in price and quality, but generally you will be looking at about 15 USD for a dorm and about 20 USD for a double / twin room (each), at the low end of prices.
The most amazing things to see when you stay in a Thessaloniki hostel involve architecture. Along with the churches, remember to check out the White Tower and the Byzantine Walls. There are also several extremely nice museums in the city which are well worth your time. The city also has a long history of Judaism, and for those interested, the synagogues and also the Jewish Museum are nice places to go and visit.