direcorty listing

Hi, I have a directory like structure below - cityname --townname ---busname ----day -----info.zip I want to write a script and let it search the directory and find the zip files open them do the operation and save the out file as cityname_townname_busname_day_info.txt I am doing it for any zip files so the last part is O.K. by now but I need a loop to go under the direcoty structure and search for them. Cause if the info file is at level 2 (I mean under the townname direcotry) than it means a brief info of the time table so it will be save as cityname_townname_info.txt I am not familiar with the direcotry functions. Can anybody help me with that? regards FB