Microsoft Windows XP
History, Downloads and Cookies
C:\Documents and Settings\{user}\Application Data\Opera\Opera\
Cache
C:\Documents and Settings\{user}\Local Settings\Application Data\Opera\Opera\cache\
Microsoft Windows Vista / 7 / 8
History, Downloads and Cookies
C:\Users\{user}\AppData\Roaming\Opera\Opera\
Cache
C:\Users\{user}\AppData\Local\Opera\Opera\cache\
Apple Macintosh OS X
History, Downloads and Cookies
/Users/{user}/Library/Opera/
Cache
/Users/{user}/Library/Caches/Opera/cache/
GNU / Linux
History, Downloads and Cookies
/home/{user}/.opera/
Cache
/home/{user}/.opera/cache/