Context:
Oldest tree in Brno is in Bystrc. It is linden older than 400 years.
Bystrc is hub of public transport incluting buses, trams and troleybuses.
From spring till autum there are electric ships serving as public transport.

Question:
When is possible to travel by ship on Bystrc lake?

OriginalAnswer:
Main season is from spring to autum

ModelAnswer:

I'm checking the opening hours of the marina on Bystrc lake. The marina is 
opened from April 15 until October 31.

So, it's possible to travel by ship on Bystrc lake from April 15 to October 31.

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