In Kingdom Hearts PS2,Im in traverse town and they keep telling me that 1st district is secure but..?

im running around the 2nd and 3 rd district and all i can do is destroy heartless and ive found the gizmo shop and some penguin looking things that i can kill also. what else do i do? and where do i do it?is there a sewer behind those wood boxes in the drainage well? is there something on the roofs, a ladder somewhere maybe? im so lost..please help with some suggestions