Not too far away, in St. Luc, in the Valais, there is a Planetary Footpath leading to an observatory. The St. Luc tourism web page describes it this way:
" Enjoy this 6 km long path situated between 2200 and 2500 m above sea level while facing the prestigious “4000” of the Valaisan Alps. You will encounter the 9 planets of the solar system built to scale on works of art. The solar system has been reproduced on a smaller scale all the way along this path, that way, with every step forward, you will move a million kilometres forward through the cosmos. Without noticing it, you will move three times faster than the speed of light. Leaving from the sun, you travel a distance all the greater that the object is remote from the sun. Whilst stopping along this celestial path, you will learn about the planets’ dimensions , their characteristics and above all be able to discover and admire the beauty of one which is only a stone’s throw away – planet Earth! Beyond the simple enjoyment of fresh air and magnificent mountain scenery, we offer you a chance to approach in a more concrete way one of the most astonishing sciences : astronomy."
St. Luc is about a 2 hour drive from Geneva. (You can also go on the train and
Post Bus.) Click here for a map.
Visitor information is available here at My Switzerland.com: "Nature lovers can access the path on foot all year round, via St. Luc or Chandolin. Stargazing evenings are organised for the public several times a year and these provide the opportunity of observing the sun and the moon."