To spark interest for the upcoming 2017 Summer Universiade, the city of Taipei has employed a fantastic marketing strategy that sees the city’s subway cars turned into realistic backdrops of several popular sporting venues. The floors of each car have been replaced by laminate overlays of track lane, grass turf, basketball courts, and baseball fields—though by far the most popular car is the swimming pool. The Universiade begins August 19th and involves 22 different sports across 70 venues. ….
Update on July 24, 2017: I found this train today (greatly helped by staff at one of the stations) and here we are!