While talking to the fisher guy in the fishing hut he told me the best place to fish was in small places surrounded be rocks or wall. 

Is this true? If so, where are theses places in the game? Is there anything else that helps to catch more fish? 

For example, I have noticed that fishing next to a fisherman seems to have a higher chance of catching something. is this correct, and what else helps with fishing?


Question: Is there a non-trivial topological group structure of $\mathbb{Z}$?
Answer: There is a topology on $\mathbb Z$ which has the set of all arithmetic sequences as a basis. It shows up in the topological proof of the infinitude of primes, cf. [H. Fürstenberg, On the Infinitude of Primes, Amer. Math. Monthly 62 (1955), 353]