Yes, it's /root on Linux Mint.
How to Get The Home Directory of Root?
To get the home directory of the root user on Linux, you can use the following terminal commands:
me> su -
Password: *******
root> echo $HOME
/root The command su - switches to a different user changing the environment variables (the dash (-) argument does this, so it's important!). The home directory's filepath is contained the $HOME environment variable, so all you need to do is echo it.