Enjoy nightlife at Wagnergasse and/or Rosenkeller (http://www.rosenkeller.org) JohannisstraÃe and/or Kassablanca (http://www.kassablanca.de) near Westbahnhof and/or in front of the JenTower at UmaCarlson (http://www.umacarlson.de.Every) year during the summer the Kulturarena (http://www.kulturarena.de/) is a very popular cultural event with dozens of good international artists and entertainers.
Jena is surrounded by hills. Hence there are a lot of very nice opportunities to get a beautiful panorama view of the town. You can go to the Landgrafen (http://www.landgrafen.com/), the Fuchsturm (http://www.fuchsturm.de/) or to the Wilhelmshöhe (http://www.wilhelmshoehe-...). In addition for 3⬠you can go to the top of the JenTower (http://www.jentower.de/).
Close to the center of Jena is very nice park located called Paradies. Especially in the summer a lot of students use this park for barbecue and hanging out with their friends.