Deutsche Bahn began resuming train services after a nationwide communications failure on Tuesday evening brought operations across its network to a standstill, several dpa reporters travelling on affected trains confirmed.
The state-owned rail operator said the disruption had been resolved and that services were now gradually resuming.
Regional and suburban rail operators run by Deutsche Bahn also said on X that services were gradually restarting, but warned that major delays and cancellations were likely to persist into Wednesday morning.
The disruption affected GSM-R, the digital radio system used for railway operations and communications across Deutsche Bahn's network.
"We were able to stabilize the situation with an emergency system. We now need to determine the cause," chief executive Evelyn Palla told Bild newspaper.
The company said it was providing affected passengers with taxi and hotel vouchers.
The outage also affected some commuter rail services operated by Deutsche Bahn, including Berlin's entire S-Bahn network.
Local operators in several cities reported service suspensions or delays, while other urban transport systems, including Hamburg's subway network, continued to operate normally.
Private rail operators were also affected. Metronom, which runs regional passenger services in northern Germany, said all of its trains had been impacted.
