The Jona is a 19 km long river in the Swiss cantons of Zürich and St. Gallen, forming partly their mutual border, and one of the main tributaries of Obersee, Lake Zurich.
The Jona is a 19 km long river in the Swiss cantons of Zürich and St. Gallen, forming partly their mutual border, and one of the main tributaries of Obersee, Lake Zurich.
