During the invasion of the Fire Nation, the invasion force approached the gates with the help of a fog cover, conjured by Katara and the Foggy Swamp waterbenders. However, their arrival was noticed, and the Fire Nation closed and ignited the gates before they could get past. Upon boarding the oncoming invasion ships, the Fire Nation military was unable to find anyone on board, as the invasion force had used the ships as cover for their submarines, effectively bypassing the gates unscathed.