The tiles in CivIII is only displayed squared but you can move eight ways. Anyway: Take two circular maps where the north pole is in the center of map1 and the south pole is in the center map2. Place map1 on its head. Place map2 on top of this. When u walk out of one map u enter the other where the ends join ... This makes travelling around the pole easy combined to travelling around the equator. But you cant do it by clicking left_arrow only. Travelling any direction and keeping that direction from one of the poles will take u directly (shortest path) to the other pole. Everywhere u go u go north or south.