)
You should know where your Steam folder is located. Since this is a Windows only game the default path of the Steam folder should be:
Windows 64bit: "C:\Program Files (x86)\Steam\"
Windows 32bit: "C:\Program Files\Steam\"
Your Rise of the Tomb Raider save files should be located at:
"Steam\userdata\<Your Steam ID>\391220\remote"
Save files of RotTR will look like this:
- lastauto.dat (Last Auto save)
- lastbackup.dat (Last Backup save)
- lastcamp.dat (Last Camp save)
- save1.dat (Manual save in slot 1)
- save2.dat (Manual save in slot 2)
- save3.dat ...
You also got:
- profile.dat (Account/Profile information)
This one is most likely also very important as it is in most games.
If you want to backup all your save files locally (which is a good practice if you care about it), I suggest you backup the whole "Steam\userdata\<Your Steam ID>\391220\" folder.
391220 is the Steam-ID of Rise of the Tomb Raider by the way.