The Yodoya Residence was a vast mansion of roughly 10,000 tsubo (about 33,000㎡) facing the Tosabori River, stretching east–west from Shinsaibashisuji to around Mitoryosuji. Today, a memorial stone marker called the “Yodoya Monument” stands nearby. “Yodoya” refers to a powerful merchant family that flourished in Osaka during the Edo period. Noticing that rice prices were being set chaotically by brokers and that quality and quantity were not being properly reflected, they established a rice exchange that became the national reference point for rice pricing, helping to stabilize confusion over rice quality, quantity, and price. The Yodoya family, whose total assets were said to be about 2 billion ryō (often described as roughly 200 trillion yen in modern value), served as official merchants to the Tokugawa shogunate. Rice trading took place at the storefront at the south end of Yodoyabashi until it moved to Dojima in 1697. The second-generation head, Koan, is known for funding the construction of Yodoyabashi himself for the convenience of the marketplace. Through ventures such as establishing rice and fish markets, domestic and overseas trade, and finance such as loans to feudal lords, Yodoya helped lay the foundations of Osaka as a merchant city. However, their financial power eventually came to influence warrior society as well, and the shogunate at one point confiscated their assets.