Wikipedia
Ankathattu
Ankathattu is a Malayalam word identifying a platform constructed temporarily for the purpose of fighting duels. It is a four to six feet high platform constructed in Kerala, South India. Ankam means war in Malayalam language. This platform will be constructed as per the tradition and will be in the center of the ground from where all peoples can watch the fight. This place altogether is called AnkaKalari.
Few centuries back in Kerala if there was a quarrel between the local rulers, it's finally solved by fixing an Ankam (war), usually a duel fighting. Each ruler will be represented by an Ankachekavar. The ruler of the Ankachekavar who wins the fight is considered as a winner.