All the important business of Iwa happens in the large buildings at the base of the Village. The building has meeting rooms for the ninja and for the Tsuchikage's personal advisers. You can report here for missions or report when needed.
This is the Board for all Iwagakure shinobi to come and request missions such as D, C, B, A, and S. The Kage will make sure that your request is tooken to as fast as he can but if he is in another village, then he cannot give you a mission. Kages are able to leave missions up on the board if they choose too.
One of the larges villages yet not quite as large as Iwagakure, Megiddo is a beautiful city made completely of glistening jewels and precious rocks. The place itself costs a fortune, it's one of the best places for market due to how many people it attracts.