By bike from St.Gallen to Rheineck.
The trail leads from the Botanical Garden in St.Gallen via Mörschwil down to Horn on Lake Constance. Here it runs along Lake Constance via Rorschach to Altenrhein, where it follows the Alter Rhein river until reaching the destination of Rheineck. Near Mörschwil shortly after Horn, you pass a small castle which is worth a short visit. Altenrhein is home to the only Hundertwasser building in Switzerland – the Altenrhein indoor market. It was built based on the idea and design of the famous artist. For technically inclined cyclists, there is an aviation museum at the Altenrhein Airport which has old-fashioned aircraft on display.
The many beaches along the route on the shore of Lake Constance are perfect places to stop for a well-deserved break. The natural environment along the Alter Rhein river is protected and home to many different bird and plant species. Finally, the small town of Rheineck has a picturesque old town and a variety of good restaurants.
The pretty bathhouse in Rorschach built in 1924 is a great place to take a swim and relax.
We highly recommend taking public transport to return to St.Gallen:
first by boat on the Alter Rhein river to Altenrhein and then across the Rorschach Bay to Rorschach where you can easily change to the train to St.Gallen. And, with the right ticket, you can take your bike with you on the boat and train. The route can be divided into any number of stages or shortened.
Current boat schedules can be found at: http://www.sbsag.ch/
Coming from Zurich: Exit at A1 St.Gallen-Neudorf