Hi Helen, and welcome to MySwissAlps!
>> I have found somewhere to stay at a farm stay in Oey Diemtigtal. We are hoping to travel by rail bus rather than hiring a car.
Have you checked out how close your accommodation is to transport? It would also be a good idea to check what time the first and last services of the day run, and the hours and frequency of weekend services (if you haven't already done so).
>> On the accomodation information it says about a naturpark card for the region which gives some discounts on travel etc.
Information about what it covers is here:
>> I was just wondering if you could give any more information on how much this costs
It is free from your accommodation provider if you are staying at least one night in the Diemtigtal.
>> Should I still look into a travel pass for travelling around?
Probably, as only limited things are covered by the card, and some of the discounts are fairly small.
There is only one way to know for sure: add up the full-fare cost of all trips you intend to do by train, bus, cable car and boat, adjust the cost of anything covered by the NaturparkCard and compare the total cost of separate tickets with the cost of doing the same trips with the Swiss Travel Pass, Swiss Half Fare Card etc.
You can find fares in the Swiss Timetable.
It is important to be aware that the fare shown for any trip in the Swiss Timetable defaults to half fare, as most Swiss residents will have a Half-Fare travelcard which entitles them to this discount. Your calculations need to be based on full fares, which are double the default fare that comes up.
There is information and a spreadsheet here to help you:
www.myswissalps.com/tr ain/ticketspasses/prac tical/chooserailpass