Can't find site directory

Hi,
i have installed a multi site wordpress. And I created 3 sites. They are in sub directories
domain.com/site1
domain.com/site2
domain.com/site3
Site 1 I will use as main site. Now I want to use sub domains for 2 of them. They are already installed. I need the path to directory, where they are, to redirect sub domain to this sites. But when I search in directory:
wp-content
they aren’t there!
How can I find the directory for each site? Where they are?