The company launched the service in the presence of Dorothee Bär, state secretary at the Federal ministry of transport and digital infrastructure (BMVI) and Maren Kern, board member of housing association BBU Verband Berlin-Brandenburgischer Wohnungsunternehmen, alongside Tele Columbus CEO Stefan Beberweil.
Tele Columbus said the speed available was about twice as fast as the top speeds previoiusly available to Potsdam residents. The cable operator has about 40,000 connected homes in the area.
Tele Columbus is offering the 400Mbps as part of a bundle that includes flat rate telephony for €99.99 a month.
The company plans to introduce the ultra high-speed service in other regions in the future.
Germany has set a goal of making a minimum of 50Mbps available across the country by 2018.