Located right next to the Hauptbahnhof station, the 4You Hostel is cozy and understated but promotes an ecological approach to lodging with solar panels, energy-saving systems, a refuse sorting and avoidance system and ecologically manufactured furniture. Added perks include a free all-you-can-eat breakfast, bike rentals, free WiFi and a bar. If planning for Oktoberfest, be sure to book well in advance.