This is a small demonstration of changing elevation during a scenario
Elevation changes are usually very easily seen when a building flattens a hill when constructing on it. However elevations can be raised too(in a limited capacity). And the changes can be controlled with triggers.
When a building is constructed on the very edge of a hill on the south and/or west side of an elevation, the terrain raises(land can even elevate ontop of water)....this can be very useful.