It will be valid 30/31days from the day that you select as startday (doesn´t have to be the first Travelday but usually it is ) For example 7thJune till 6th July within this period you have to take then your 7 Traveldays :)
 

Thank you Seewulf. Your answer helps our planning very much.

Validity is 1 month to be exact. So if the first day of validity is e.g. in July or August, then it's valid for 31 days :)

Traveling from California, first country is Spain (Madrid September 5th), on to Barcelona (September 7th), then on to Switzerland (September 10th), where I plan to be for several days and travel internally. What counts as a travel day? is travel within the same country on local transportation included?

Hi, a travel day is 24 hours. For more information you can have a look here. Trains and some ferry routes are included or discounted. Other modes of transport are not included in the Pass. There are a few exceptions included as benefits. Here, you can find all benefits per country.