Under Japanese rule the Ryukyu Kingdom established signal fires which were in important strategic positions and quickly transmitted information on the arrival of foreign ships. On the Sakishima Islands (the Miyakojima and Yaeyama Island groups) fast ships were equipped for urgent communications with the government as well. Domestic transportation networks were formed around Naha, the trading center for provisions as well as the major port of the Ryukyus. Inns to stay at were called Magiri Yado, Shima Yado, or Mura Yado and were often crowded with people because public officials frequently came over to Shuri and Naha on official business. A main road connecting the jurisdictions was called the Shuku Michi (Inn road). Administrative orders were conveyed along this road to each district from the government of the kingdom. The roads of throughout the Ryukyu kingdom developed and spread around this Shuku Michi.