If you move into a flat in Frankfurt am Main, you must register in person within one week. All information on this, applications and contact details can be found on the website of the City of Frankfurt:
Frankfurt is not a typical university city, but much more. However, Frankfurt is also not a city of millions, but has grown together from smaller city districts with over 750,000 inhabitants. Despite its impressive skyline, Frankfurt is also not a concrete castle, but a city with extensive green areas and parks extending into the city centre. Frankfurt residents love their city's unique combination of cosmopolitan flair and almost tranquil idyll in the city districts.
A great advantage for students is the very well-developed underground, tram and bus system in Frankfurt. Enrolment automatically includes the purchase of a semester ticket, which covers not only the inner-city transport system, but also the greater Frankfurt area and many regions throughout Hesse.
If you want to get a nice room close to campus, you should start looking for accommodation early. The average price per square metre for rental flats is between 13 and 18 €/m² (source: Mietspiegel immowelt.de). Rents are usually cheaper in the Frankfurt environs.