The U.K. also had some 3kV DC years ago. Although that went out of use, didn't somebody in here (Hutch?) mention that it had been re-introduced in some of the new city "Metro" systems?
The old "tram" (street-car) and "trolley-bus" systems here ran on a nominal 500V DC in most cities. I assume that the famous trams in Blackpool still use that.
