To relocate your base next to your alliance, you can follow two methods: 

-Use the "Alliance Relocation" item from your inventory. This item relocates your base to a location closer to the alliance leader. You can obtain it from the alliance store if it is available or as a reward from certain events.
-Click on the Alliance icon at the bottom left of the screen, then choose "Alliance territory." You will see the forts of the alliance, along with their locations.
-If you have your alliance coordinates (X, Y), you can put them in the box with the magnifier at the bottom of the world map screen. This way, you will be transported to the desired location, and then you can move your base manually.