The good thing about Heilbronn being a smaller city in comparison to Stuttgart, is that moving around is not that complicated and it doesn’t takes too much time to reach places.
To move around in Heilbronn you can use the Bus, the Train, Bicycles and of course by car.
The thing with buses in Heilbronn, and probably around Germany, is that they are not always on time as they use to. It is recommended to download the Deutsche Bahn app to get the time schedule of the buses.
As well, if there are people studying at Europaplatz and need to go to Sontheim Campus, usually there is only one bus line (40) that connects both areas.
Using the bike is one of the most common transport to be used in Heilbronn. There are some streets that have the proper bicycle signs, but sometimes it gets confusing since it gets mixed up with bus lanes.
The S-bahn is mostly used only for a sector of the city, since it only have stops in main areas of Heilbronn like the Rathaus, Finanzamt, or even Kaufland in the northern area.
If you are planning to eventually get a car, you will need to validate your driver license or do the process to get your german driver license. There are some driving schools around the city that can be attended to start the process. It will require a theoretical exam, first aid course and the practical driving hours and driving exam.
Travelling within Germany is easy and is cheaper if you travel with friends with the Schöneswochenende or regional ticket.
Moving around the country within the train is simple and you can cross practically whole Germany with it.
As an alternative to use the train there are buses such as Flixbus. These buses are cheap, but sometimes the quality of the travel is not the best. Besides the advantage of the price, using such buses are even more convenient than trains since sometimes they have less connections or hop-offs.
Also, the app Bla Bla Car is useful when there are drivers who are willing to share a trip for a lower amount of money than trains. The disadvantage is that one has to be dependent on the driver and the availability of trips. Sometimes in places like Heilbronn there are not to many trips, or if people pass near Heilbronn, they might ask you to meet in places closer to the Autobahn, near Neckarsulm
Using flights inside Germany would take too much time in the case of Heilbronn. Since you will have to take into account the time that you go to Stuttgart, which is the nearest airport and it takes around 1 or 2 hours. Then you will have to wait at the airport for the flight, around 2 or 3 hours, the flight time, around 1-2 hours and the time you do from your destination airport to the city center less than an hour. So added up, it could be a trip of 6-9 hours. Therefore, it might be better to consider ICE to move faster with a train.
In contrast to taking a national flight, an international flight sounds better to invest that amount of time.
As the previously mentioned process, Heilbronn doesn’t have an airport, but it could be considered to be in a good position to choose to travel from different airports, such as the one from Stuttgart, Nurnberg, Frankfurt or even Karlsruhe.
There are plenty of low cost airlines that can be taken from those airports. Usually some flight destinations of Ryanair are not available in Stuttgart, but are available in Frankfurt or Nürnberg, therefore it would take almost the same amount of time or an hour more to arrive to those airports from Heilbronn.
An alternative to move around Europe is to use as well buses such a Flixbus, but I will recommend to use it if the destinations are relatively close.
As well, there are train tickets such as Eurail, that offer packages to travel around European countries.