Replying publicly because this may be useful to others trying to find old streets or other information about Poland or for that matter any other non-English-speaking country.

Steve,

A small trick I’ve found extremely useful in trying to find old Polish streets or other details specific to Poland is to go into POLISH Wikipedia and search. You can often find information there that just doesn’t exist in English Wikipedia or other English sites. This is equally true for any other foreign country — for example, searching in French Wikipedia for French streets or other information about France. I then use the automatic translation or copy and paste into Google Translate to see the information in English. (We all know that Google Translate isn’t perfect, but it is good enough for the purpose of understanding a Wikipedia entry in a foreign language.)

In your case, I found the answer almost immediately by searching for Ulica 6 Sierpnia Kalisz in Polish Wikipedia. This took me to an entry showing that the street has been renamed a number of times and since 1990 has been called Zamkowa.

There is a detailed history of the street in the Polish Wikipedia entry should you wish to read further. 

As for your comment about the bank being in Lodz, I recently discovered a similar file for my own great-aunt, whose whereabouts before the war I didn’t know, although I knew she perished in the Holocaust along with her husband and children. I ordered the file from the State Archives in Lodz and it revealed that they lived in Lodz and had a tailoring business there in the 1920s, but moved to Kalisz around 1930, where they lived in Ciasna street. This was a revelation to me and led me to further research and the discovery of her previously unknown children’s names, whom I can now commemorate properly. So I  strongly recommend writing to the archives and getting the file to see what it contains. 

Once again, I used Google Translate both to write to the archives in Polish and to understand their reply. The fee for documents is small but unfortunately they do insist on being paid by direct bank transfer, which adds to the cost in bank fees. Still, to me it was worth it.

All the best,

Miriam Bulwar David-Hay,
Raanana, Israel.