Lower Saxony

There is a special ticket called the "Niedersachsen Ticket" (http://www.bahn.de/i/view...) which offers unlimited travel by regional trains inside Lower Saxony area, up to Bremen and Hamburg in one day. This ticket is not valid in high speed trains D, EC, IC, ICE so make sure you board the right trains RE, RB, S-Bahn, Metronom when using this ticket. It is valid from 9am to 3am the following day during weekdays and the whole day on weekends. There are many types of tickets, the group ticket up to 5 people, €37 and the single ticket €21. These tickets are also valid inside public transport network in some of the cities Hanover, Hamburg, Bremen, Brunswick.