Storage lockers in Interlaken train station

There are lockers at Interlaken Öst ( we used them ), but you must understand that most lockers Swiss train stations have a 48-hour maximum ( or possibly 72). So you can 't use them to store luggage for ten days. You need either a manned "left luggage" storage, or a hotel willing to keep it for you until your return. If you stay at the same place before and after your hike that might work. You should ask in advance when booking.

There is a left luggage office at Interlaken Ost Station next to the ticket office.

Is it possible to store luggage luggage there for an extended period, a week or more? And what is the cost? Many thanks.

Dine, I can't answer your question, I would suggest you email Swiss Rail and ask them