Giessen (Gießen) is a city in Hesse.
The city has about 78,500 inhabitants including 30,000 students, so its infrastructure, shopping and cultural offerings are pretty well adapted to that.
Nearby are some old castles , which can be visited too.
Giessen is home to Justus-Liebig University .
There is a McDonalds restaurant outside one of the main gates. There are actually fast food restaurants everywhere.
But if you prefer non-McDonalds food, there is an italian restaurant "Adria" in the Frankfurter Straße and a greek restaurant called "Bakchos" in the city centre, near the Marktplatz.
Youth hostel in Gießen  , about 20€/night