Romanshorn railway station, opened in 1855, forms the junction between the Winterthur–Romanshorn railway, the Schaffhausen–Rorschach railway and the Romanshorn–Nesslau Neu St. Johann railway.
Frauenfeld railway station supports a regional train, part of the Zürich S-Bahn, from Weinfelden to Winterthur (S8 and S30) every 30 minutes, as well in the opposite direction and a fast train (InterCity and InterRegio) that travels to Zurich every 30 minutes, as well in the opposite direction to Weinfelden and further to Constance in Germany or Romanshorn.
In the same year, the Lake Constance train ferry was established, for cross-border goods traffic to and from Germany between Romanshorn and Friedrichshafen, and between Lindau and Bregenz.