Guaymas, city and port, southwestern Sonora estado (state), Mexico. Located on a bay of the Gulf of California, it lies at an elevation of 13 feet (4 metres) above sea level and is surrounded by mountains. The city was established in 1769, and in the 19th century its port became one of the most important in northwestern Mexico. As a result, Guaymas was a strategic prize during the Mexican-American War (1846–48), a filibustering expedition of William Walker (1853–54), the French intervention (1861–67), and the Mexican Revolution (1910–20).
Guaymas remains a centre for shipping, commerce, manufacturing, and tourism. Among its chief exports are copper, sulfuric acid, and wheat and various other crops grown in the hinterland (notably cotton, fruits, and vegetables). Seafood-processing plants are located in Guaymas, but overfishing and a lack of fresh water from the Colorado River have caused a decline in its fisheries, especially for shrimp. The city is still known for its sportfishing (sailfish, marlin, yellowtail, and others), however. Resort developments along the Gulf of California north of the city, especially at San Carlos, are transforming Guaymas into a major tourist destination. Guaymas is linked to the Mexican interior and the U.S.-Mexico border by railroads and highways and is served by an international airport. Pop. (2010) 113,082; metro. area, 203,430; (2020) 117,253; metro. area, 208,294.