After photographing Transportation Bureau, City of Yokohama 4000 Series, I also did 10000 Series on Yokohama Municipal Subway Green Line.
Since 2008, 4-carriage 10000 Series has been in service. But in 2022, some sets of 10000 Series started to couple more two carriages.
On that day 10031F set was in service.
The third and fourth carriages in the photograph are newly-made. In addition, the "6 cars" sign is showing on its front. By March, 2025, the newly-made ones will be added to the ten sets.