Strasbourg

Strassbourg is one of the bigger cities of France. It is the siege of the European Parliament, and pretty bourgeois.

In theory it seems doable to hitchhike directly from the centre, as there is the entrance to several highways. However, the people of the city are not very hitchhike-friendly, so it is better to directly go to a gas station on the highway.

For going north

Go south, taking tram A (I forgot, please confirm someone), right to the end of the line. From there you walk west for a while, and then you can find the gasstation on the side to go north. (I'll upload some pics :)

For going east (Germany A5)

You can take the regional train going to Kehl which is already in Germany. (around 6mins 2-3EUR). In Kehl you've got a big road going directly to the motorway A5 - and everyone who's coming from France is using this road. You also find a gas-station!