This is Duvbo station in the Stockholm Tunnelbana system. Compared to Stockholm's bigger stations, it is simple and mostly monochromatic. The platform's red "Y" columns and overhead structure provide the only color in the station. The stripes on the floor are the only other design element and, overall, it is dark and featureless.
I explored the station, but I did not find a reason to photograph it until I saw the next train arrive. The additional flash of light & color from Stockholm's blue trains made the scene much more interesting. As there was only a short wait between trains, I attempted to capture the scene with this extra element.
I stayed here for about 20 minutes, snapping 3-second exposures of several trains arriving & leaving on each side of the platform. There was not a moment when two trains were in the station at the same time. However, with a simple blend of 2 images, I was able to place a moving train from different points in time on each side.