Are you sure there is an "n"? It could be Krockow instead:
Alt Krockow (German)/Stary Krokowa (Polish) is a village in the province of Pomerania in northern Poland. The area was formerly Prussia.
The English Wikipedia page is very short (http://en.wikipedia.org/wiki/Krokowa
) but the German and Polish versions are much longer, so you could run one of those through a translator if you don't mind grammatical errors to get a better sense of the village and its history.