When we arrived in Seville, we first saw a tall tower on the Bank of Guadalkivi River, the Golden Tower. The Golden Tower is a 12th-13th century building. It is Arabic-style, 12-sided. The Guadalkivi River is Spain's largest inland river. Seville is also the most important inland port city. The treasures brought back by Columbus conquering the world were unloaded here and transported back from South America. It was also transported from here to Europe, where it was in charge of the East India Company, the most important trading company in Spain's trade with Asia. Later, due to the siltation of the river, the port was changed to the port of Alkhsilas in the south of Spain, and the economy of Sevilla was declining gradually. It was not until the Ibero-American Expo was held in 1929 that the economy of Sevilla was revitalized. The Golden Tower was the witness of that glorious period. The name of the Golden Tower is that it was covered with gold powder and that it was the landmark of the unloading place of gold and silver. I feel that the latter is probably more reliable.