The Swiss Alpine Pass Route runs for 200 miles between Sargans and Montreux over 18 mountain passes.
My wife Jan and I walked it with 3 friends in two 8 day sections, the first from Grindelwald to Montreux in 2006 and the second in 2013 from Sargans to Grindelwald. Both trips were in Late August/early September.
I wrote daily blog posts at the time and have combined these, illustrated with mobile phone pictures as well as the black and white photographs that I took on my Mamiya film cameras. There’s lots of other information there as well.
Here’s the link to the webpage: