Your Mine produces iron for your town and is one of the five resource generating buildings in Vikings War of Clans.
Upgrading your mine increases your iron production per hour. It also increases your town’s total iron capacity. Your capacity limit does not stop you from holding more iron, but once you reach this limit your mines will stop producing iron for your town. Once your iron stores drop below your capacity limit, your mines will start producing again.
Building 4 mines will complete a quest rewarding you with influence and resources.
The table below has the build cost for each upgrade level from 1 to 21, the Palace level required, time to build (before boosts) and the influence reward.