Ultimate Guide to Warrior Cats Herbs, Terminology, Etc.

6: Gatherings

On Gatherings, Clan leaders announce current affairs and significant events within their Clan (like appointing new apprentices and warriors, or death or birth of a cat). They also use this time, if necessary, to ask for help from others, such as when WindClan asked RiverClan for drinking rights in their territory, when a drought shortened their water supply.
Warriors use this chance to meet their friends from other Clans and exchange information. Many cats will use a Gathering to try to determine the strength and weakness of another Clan.
Clan leaders hold Gatherings to share news with the other Clans.
Gatherings are meant for meeting new cats, but not to share Clan weaknesses and strengths.
When the moon is full, the Gathering begins.
The start of the gathering marks a time of truce between the four Clans. When the truce is broken StarClan voices its displeasure by sending clouds over the moon. Then the Gathering is over and the Clans must go back to their territories.

Procedure:
The Gathering is held on the night of the full moon, because it is the only time that the moon is bright enough to see everything and everyone. The leader, the deputy, the medicine cat and apprentice, several warriors, apprentices, and elders participate from each Clan. If a leader cannot attend, the deputy will speak on behalf of their Clan.
Once arrived at the Gathering territory, the leaders sit on a designated high spot (i.e: a rock or a tree branch) along with the other leaders where they can be seen and heard well while talking to the warriors and to each other. Deputies sit close by. It is considered to be disrespectful if any other cat speaks from atop the leader's spot, unless specifically asked.
As decreed by StarClan, the nights of the Gatherings are a time of peace. If there is any violence, StarClan sends a cloud to cover the moon signifying their displeasure; usually the Gathering ends if this happens.
In The Sight, the Clans organize a special daylight Gathering, with friendly competitions between the apprentices of different Clans. This was to ease the tension between the Clans, which was unusally high.

Location:
The Gatherings are held on neutral territory, unclaimed by any Clan.

Old Forest:
The Gathering was held at Fourtrees, where the territories of all four Clans meet. There were four great oaks there, older than the Clans. The leaders sat on the Great Rock, which was a huge, smooth rock in the center. They could sit there and look over all the Clans. Deputies sat a the foot of the rock, while medicine cats sat at the edge of the clearing.

Lake:
In Twilight, the Gathering was held near Horseplace before the tree fell down, therefore, making the tree a bridge so the cats could get to the island.
The Gathering was held at the Island, a place near the side of the Lake by RiverClan territory. Mudclaw was killed by a falling tree on the Island, making a tree-bridge, since RiverClan was the only Clan who was used to swimming. Because the tree-bridge was only on RiverClan territory, the cats made it a rule that scent-marks end three tail-lengths from the shore of the lake, and that three-tail-lengh area was neutral territory.
In Dark River, RiverClan used the Gathering Island temporarily as a camp, when Twoleg kits were playing around the camp. The RiverClan cats had a simple plan of throwing rocks into the river to make it deeper and wider to deter the Twoleg kits. Neverless, the whole incident created an uproar among the Clans.

Other Places:
In the The New Prophecy series, it was once held at a marshy place near Horseplace.
In the Power of Three series, it was once held in daylight in ThunderClan territory Abut it was competitions and contests.
When foxes took over Fourtrees, the Gatherings were held at Snakerocks.
In Firestar's Quest and SkyClan's Destiny, SkyClan's Gatherings are held on the Skyrock