Where can I find clan wars?

If you are in a clan, you can access clan wars at any time via the clan wars button on left bottom corner on your screen (the button with two swords crossed). From here, new clan wars can be started by clan leaders and co-leaders, and you can participate in or spectate any clan wars that are in progress. If a clan war is in progress, pressing this button will take you directly to the map of the war zone.