FrOSCon offers you, in cooperation with Deutsche Bahn and CCC, train tickets at special fares.
Deutsche Bahn offers you a discount on the normal prices (FLEX Ticket). If cheaper options are still available, you will get an offer for these, too.
Please note that you have to “buy” a free ticket for FrOSCon to be able to use DB event ticket.
Possible targets for FrOSCon are Siegburg Bonn and Sankt Augustin Zentrum.
More details and booking.