opera://settings/?search=location
you can test it here:
http://benwerd.com/lab/geo.php
From 2011, but still has some nice info on the topic http://www.brighthub.com/internet/security-privacy/articles/107985.aspx
I should add that some websites use ip address to track your geolocation, but that only give an approximate location such as the city where you are from.