The hall of the city guilds. Here are the Court of Common Council, the Court of Aldermen, the Chamberlain's Court, the police court presided over by an alderman, etc. The ancient guilds were friendly trade societies, in which each member paid a certain fee, called a guild, from the Saxon gildan (to pay). There was a separate guild for each craft of importance.
“Gild [guild] signified among the Saxons a fraternity. Derived from the verb gyld-an (to pay), because every man paid his share.” —Blackstone: Commentaries, book i. chap. xviii. p. 474 (note).