Zurich Airport is the main international gateway, about an hour by train from Frauenfeld or Kreuzlingen. SBB intercity trains run hourly to Romanshorn and St. Gallen; the Thurbo regional services link these into the smaller lakeside towns. From Germany, the IRE from Stuttgart serves Konstanz, from which Kreuzlingen is a 10-minute walk across the border.
By car, Thurgau is on the A1 motorway between Zurich and St. Gallen. From the German side, motorway 8 (Stuttgart–Munich) and the A98 (Karlsruhe–Bregenz) both feed into the lake's northern shore, from which the car ferries at Friedrichshafen–Romanshorn and Konstanz–Kreuzlingen complete the crossing.