Even though it was pouring with rain, this was fascinating. You will need to allow plenty of time as there are 46 rooms to go through and the connecting stairways and passages all make the experience very interesting and fun. On our visit, the only rooms that were heated were the museum and the café so it did get very cold but I understand from friends that they normally do have heaters on in some of the rooms.
The café in the castle is only a coffee machine, another drinks machine and a few tables and chairs.
If you want food, there is a fantastic little restaurant just up from the castle entrance called "Restaurant Taverne du Château de Chillon" which serves a very wide variety of excellent food.
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