Copy the ID of the location you with to link to...ie, rally point, forum or whatever. Go to your account, preferences. Name the link...insert the id on the left side..go to bottom and click save. Many are possible. It is really convenient when with all your villages you put the same building in the same space...such as the rally point is structured. Then you can just quickly click a link to go direct to the market no matter which village you are in.