4n 5 day trip to Switzerland in May

Hi,

I am from India. We are planning our first trip to switzerland and plan to spend 3 night in Wilderswil ( 1 st - 3rd May ) and 1 night in Zurich ( 4th May ). We are a family of four with two children - 19 years and 15 years old. Request your advice on the following :

1. Please advice the route from Innsbruck to Wilderswil by train on 1st May ... most economical way to travel . If we have to take the Glacier express what is the route ? Is it more expensive than regular train ? Do we need reservations on the Glacier express?

2. We plan to visit Jungfrau, Mt Titlis, Mt Pliatus, Interlaken and Lucerne plus local sightseeing in Zurich over our trip. Can you advise on the best itinerary ?

3. Which rail pass in Switzerland will be the best for us ? We depart back to Bangalore on Zurich so we have 5 days in Switzerland. A 8 day pass would not make sense ? Should we go for a Family card... is the 15 year old child travel free with this option ?

4. On what sectors do we need mandatory reservation ? Do we have to do it in India itself ?

5. What is the best way to travel from Wilderswil to Zurich airport? we are staying at Hotel Moevnpick at Zurich airport?

thanks in anticipation