The conference venue is the Seminargebäude (“seminar building”) of the University of Cologne (Building 106, Universitätsstraße 37, 50931 Köln). The next tram stop is Universität (line 9). Inside the building, signs will lead you to the conference room.
All of the following upmarket hotels offer special conditions for visitors of University of Cologne: Hotel Hopper, Hotel Flandrischer Hof and Hotel Conti. For discount mention that you are taking part in the Summer School event at the University of Cologne, when booking a room.
Further information concerning hotels and the city in general can be found on this website: http://www.cologne-tourism.com/