Deutsche Bahn expects long-distance traffic to be severely disrupted until late in the afternoon.
She announced this on Sunday morning.
The north is particularly affected.
The reason is a cable fire in Hamburg on Friday, which made lengthy repairs necessary.
The transport company advises travelers to find out about their connections before departure on the railway website or by calling the travel information service.
The ICE trains Kiel/Lübeck - Hamburg - Hanover - Kassel-Wilhelmshöhe - southern Germany are still canceled between northern Germany and Hanover Central Station, the ICE trains Kiel/Hamburg - Hanover - Frankfurt/Main - Stuttgart/Switzerland start or end in Hamburg.
The EC trains Hamburg - Berlin - Dresden - Prague end or begin in Berlin.
The ICE trains Hamburg - Berlin - Erfurt - Munich only run once an hour between Hamburg and Berlin.
Local transport in Hamburg is also affected.