Tournament Galleries
Jousts and Tournaments: Charny and Chivalric Sport in 14th Century France

The Book of the Tournament

Tournaments: Jousts, Chivalry and Pageants in the Middle Ages

Knights at Tournament

Tournament

The Medieval Tournament

The Tournament in England, 1100-1400

The gallery is a sort of structure, usually raised and covered, where spectators would watch the tournament – usually notable spectators, like the tournament's sponsor, honorees, ladies, or marshalls. (The Middle English term seems to be “scaffold.”)

See these links for ideas on constructing temporary structures made to resemble galleries.