Estación Abando is still a working railway station, but it earns a look even if you are not catching a train. The main hall is known for its large stained-glass window, a bright mid-20th-century composition showing Basque industry, rural labour, sport, and civic identity.
It is a short stop, and that is fine. Bilbao is full of heavy-hitting architecture, from Casco Viejo churches to the Guggenheim, but Abando gives you a more everyday version: public art embedded in transport, seen by commuters as much as visitors.