The University of Sofia is the biggest one in the country, and few years ago was the only one. Now there are a lot of different colleges and universities but back then in the years this was the only one.
      It is located in the downtown Sofia too (seems like all important buildings in Sofia are in the center of the town) next to the Parliament. It was build long time ago bu two brothers with their own money. Right now it is very hard to get into it because of the hard exams that you have to take. There is a very low fee (but not low for the Bulgarians) that every student must pay.