The Zürich–Baden railway line is a major railway line in Switzerland connecting the cities of Zürich and Baden. It forms part of the major east-west route between Zürich and Olten. The line generally follows the south bank of the Limmat from Zürich to Baden. A new line, the Heitersberg line, opened in 1975, branches off in Killwangen-Spreitenbach and follows a more southerly route through the Heitersberg Tunnel towards Olten. The Zürich–Baden railway is electrified at 15 kV 16.7 Hz and much of it has four tracks.

Killwangen-Spreitenbach railway station is a railway station in the municipality of Killwangen in the Swiss canton of Aargau. As the name suggests, the station also serves the adjacent municipality of Spreitenbach.