First, the Finnish nature is really beautiful in this part of Finland. The monastery is a very interesting place to visit, even to pop in for a coffee or for lunch if you are in the neighborhood. The buffet lunch is very reasonably priced. You should visit the church and maybe the exhibitions also, depending how much interest you have in religion in general. Note that if you are not familiar with orthodox religion, it is a good opportunity to see and feel a glimpse of it. There is also a shop which sells e.g. wine produced in the monastery and handicraft.
If you have time take also the cruise on the lake with M/S Sergei. It takes about two hours, you will be taken to Varisvesi and back, on your way you will travel also in a canal and through locks. But most of all you have a chance to enjoy the beautiful scenary on the lake(s).
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