E part of Genève lake. ( LEMAN LAKE) between: Vevey and Montreux. It's about 80 km at the East of Geneva.
It's more easy to use a boat to came on the top of the site. One possibility is to use
http://www.montreux-divingboat.com
more information about the area:
http://www.swiss-riviera.com/riviera/