Mines:EditMines are an additional way to earn income even when you are offline.
Silver mines are located in every region. Simply click the region button, then either cycle through the pages to the first 3-5, or click the button "silver" at the bottom middle of the screen next to your chat box. You can also manually type in the district number.
You can either assault someones mine or take a mine that is controlled by terribly weak NPC bandits. Mines are held for periods of 4 hours. The amount of silver earned is dependent on the level of the region you are in as well as which page the mine exists in. During the 4 hour period, silver is earned every ten minutes, but is not received until the end of occupation. Once the 4 hours is up, you are automatically given the silver. You also receive mail telling you how much silver was received.
The mines in the center and close to the center of the first page have a higher silver output than the mines around the edge and on subsequent pages. The mines in the center will almost always be controlled by the strongest players of the region, so if you're not confident in your strength, avoid attacking them.
Taking a mine from an another player has no advantages over taking a mine controlled by bandits. The only reason to assault another players mine is if it has a higher output than the empty mines. It is considered rude to steal a players mine when there are empty ones of equal output available.