If you travel to Larissa by train, please consult the TrainOSE route timetable. The trip from Athens to Larissa takes about 4:15 hours, while from Thessaloniki it takes 1:25 hours (Intercity times).
If you travel to Larissa by coach, you will find useful the Larissa’s Coach Station site.
Of course, traveling to Larissa by car is very convenient since the city is on the main National Road (PAThE). It takes about 3:45 hours driving from the Athens International Airport to Larissa (a little more from Athens’ center). The trip from Thessaloniki to Larissa will make you older by 1:30 hours. Traveling by car is not the cheapest way if you are traveling alone. Apart from the fuel cost you should also consider the toll rates (there are Android apps to help you on this).
If you are coming from abroad, you will probably fly to either Athens or Thessaloniki. The nearest airport to Larissa though is the Nea Anchialos National Airport (is less than an hour driving away from Larissa). This airport serves mainly charter flights – so check it out if it fits your case.
Moving around the city with urban transportation is very easy although you don’t have to use it, since most of the “action” takes places in the city center and everything is within walking distance. If you stay in the city center, consider using bus number 9 which enters (and ends) into the TEI of Thessaly campus. Taxis are also an option – there is a taxi station inside the campus (241 066 1414).
For a quick view of the city, if you are short of time, consider using the cultural route, if available.
Free car parking in the city center in rush hours is rather a dream, so avoid city center unless you are happy with using private parking facilities (there are two big underground park stations in the city center).