The city proper is mostly an industrial port, with nearby San Carlos being the major tourist attraction for its beaches. The city also has a well-attended annual carnival, which has been held since 1888.
Before the arrival of the Europeans, the areas now known as Guaymas was dominated by the Guaymas, Seri and Yaqui tribes. In 1539, two Spanish ships, the Santa Agueda and El Trinidad, arrived in Guaymas Bay. They were commanded by Francisco de Ulloa, who called the area “the port of ports.”
Some small Jesuit missions in the area were founded in the 1610s and 1620s, when Jesuits founded eight mission villages with the Yaqui. The Seri strongly opposed the settlement of Europeans and resisted fiercely until 1769.
Juan María de Salvatierra and Eusebio Kino asked for permission to evangelize the area, which was received in 1697. In 1701, Salvatierra came to this area and established the Loreto mission somewhat inland from where Guaymas is now. To receive supplies by ship and evangelize the Guaymas Indians, the Jesuits founded another small mission on the bay, which they called San José de Guaymas. It was headed by Manuel Diaz. The Seri repeatedly attacked the San José mission, forcing it to be abandoned and rebuilt several times. The last time this mission was abandoned was in 1759.
In 1767, Viceroy Marqués de Croix ordered a major military offensive, the Sonora Expedition, to subdue the Seri and Pima tribes. After doing so, the Spanish colonials built an adobe fort with four towers in Guaymas, initially under the command of Captain Lorenzo Cancio. No traces of the fort remain today, but the San José mission is marked by a church located on the road leading to Empalme. Around the same time, the colonists formally mapped the Guaymas Bay and officially founded the city of Guaymas in 1769 by José Gálvez in Real de Alamos on behalf of the viceregal government. Despite the decree, no colonists settled there until the early 19th century.
In the late 18th and early 19th century, there was supposedly only one inhabitant in Guaymas, called “Tio Pepe” (Uncle Pepe), who was said to be a drunk and a thief. At the beginning of the 19th century, the village began to be populated by farmers and ranchers, who held large properties but did not have markets for their products. Farming was on a subsistence level. In 1811, commercial maritime traffic was authorized, and customs were established later in 1823. Guaymas received the name San Fernando de Guaymas in 1820. Ships visited the bay intermittently but only one house was here for customs purposes. In this era, it was safer to travel by sea than by land; Guaymas became an important stopping point for those heading north or south. The first commercial imports came through here in 1827. With the population of the area by European-Mexicans, the Guaymas moved to a town called Belén. They eventually disappeared as a distinct group.
The port became a municipality in 1825. During the Mexican American War, American warships such as the Portsmouth, the Congress, the Dale and the Argos anchored here near the Pajaros Island and the Almagre Grande. The ships fired on the town and captured it, keeping it in U.S. hands from 1847 to 1848.
In the mid-19th century, Guaymas was the target of several filibusters, or unauthorized military expeditions from foreign nations, designed to foment rebellion. One was done by the crew of the English sailing vessel “Challenge” and a French ship named La Belle commanded by Count Gastón Raousett-Boulbón, who intended to take over all of Sonora. The French attacked the city on 13 July 1854, but the port was successfully defended by José María Yáñez. A firing squad executed the count soon afterwards. The national government elevated the town to city status as a reward for this action in 1859. Later, in 1935, it gave Guaymas the title of “heroic city” for the same action. The municipality’s formal name of Guaymas de Zaragoza was authorized in 1862. In 1865, French ships arrived to attack Republican forces, which were forced to retreat. The French occupied the city until 1866.
By 1890, the city had 10,000 residents and was relatively prosperous. The Carnival tradition it established then continues to this day.
On October 4-5, 1911, Guaymas was struck by major hurricane and accompanying storm surge which killed some 500 people in the city and environs.
During the Mexican Revolution, the first ever aerial bombardment of a naval target occurred just off the coast of Guaymas: in 1913, five military ships belonging to Federal forces appeared in the bay, and General Alvaro Obregon of the rebel army ordered the bombing of these ships using the aircraft “Sonora.”
The first modern port facilities were built in 1925 for the Mexican navy. In 1942 a commercial pier and warehouse were built at La Ardilla. Guaymas’ importance as a port grew in the 1950s, and in 1961, a pier for the national oil company PEMEX was built. A naval ship repair station, called the Varadero Nacional, and silos for the export of grain, called the Almacenes Nacional de Depósito, were built in 1964.
Ferry connection with the city of Santa Rosalía, Baja California Sur was established in 1972. In the 1980s, a number of private construction projects further enlarged the port, including those built by the Compañía Mexicana de Cobre, Cementos Tolteca and Compañía Mexicana de Ácido Sulfúrico. Due to changes in Mexican maritime law, a private company under contract to the government, Administración Portuaria Integral de Guaymas, took over port operations in 1995.
Guaymas has a desert climate (Köppen climate classification BWh), with hot summers and warm winters.
Guaymas is basically an industrial and shrimp-fishing port which has conserved a number of historical attractions. Buildings in the historic center have a mix of Neoclassical and Moorish facades, however many are in disrepair. The city has two main plazas, one called 13 de Julio, which is nicknamed the “plaza de los flojos” (lazy men’s plaza) for the large number of people who relax there. In the 13 de Julio Plaza there is a monument commemorating the defense of Guaymas by General José María Yáñez against a French incursion in 1854. The most famous person in this plaza is León Riso, who has spent fifty-five years here selling homemade ice cream. The Moorish style kiosk in the center has deteriorated due to the humidity. The town’s main church, San Fernando, built in the 19th century, faces this plaza.
The other major plaza is the Plaza de los Tres Presidentes with statues of Plutarco Elías Calles, Adolfo de la Huerta and Abelardo L. Rodríguez all of whom are from near Guaymas. Facing this plaza is the Municipal Palace and a small concrete pier with the Statue of the Fisherman, on which is the lyrics of the song “La Barca de Guaymas.” This statue is considered to be emblematic to the city.
Other landmarks include the old Bank of Sonora building with its Neoclassical facade, the old jailhouse built in 1900, the Casa de las Conchas (House of Shells), which has a large collection on display and for sale, and the Casa de Cultura (Cultural Center), which offers classes and workshops in various arts.
Institutes of higher education in the city include the Instituto Tecnológico de Guaymas , the Instituto Tecnológico de Sonora, Guaymas  and the Universidad TecMilenio Guaymas 
Baseball is a popular sport in this city. The local professional team is called the Ostioneros. The city has ferry service to Santa Rosalía, B.C. and an international airport. As it is between the sea and ranching country, the city’s cuisine includes both seafood and beef specialties such as fish tacos and carne asada
Guaymas holds one of Mexico’s major Carnival celebrations, and is one of the oldest in the country. The annual event begins on the Thursday before Ash Wednesday and ends at the stroke of midnight of the beginning of Lent. Events are held in several locations with a number of events, such as the yearly parade, extending over multiple days. It begins with the Quema del malhumor or Hoguera, when an effigy of something or someone who has displeased the public is burned. Each year, the effigy represents something different. In past years, the effigy has represented the figures of Carlos Salinas de Gortari, Vicente Fox, George H. W. Bush, Mexico’s value added tax and lack of water. In 2009, the effigy was of singer Julio Preciado for his poor interpretation of Mexico’s national anthem at the recent Serie del Caribe baseball tournament. Other major events include concerts by regionally and nationally known artists, a multi-day parade with floats and the election of the King and Queen of the Carnival.
The history of Carnival in Guaymas begins after the Reform War and French Intervention in Mexico, when Guaymas and the rest of the country experienced a period of peace and economic development. The success of Guaymas’ port attracted a number of European immigrants and visitors. They brought the idea of organizing a Carnival similar to those celebrated in Europe. Guaymas’ first carnival is recorded in book called El Viejo Guaymas (Old Guaymas) written by Alfonso Iberri. It was one of the first to take place in Mexico. In 1888, the first Carnival Queen was María Zuber and the first King was Alfredo Díaz Velasco. The King and Queen were paraded on the streets of Guaymas in a coach, followed by coaches carrying their entourage. The event ended with a grand ball that night.
Initially, the Carnival event was restricted to the upper classes. The lower classes watched the annual parade, but the most important events were the balls given at various mansions. This tradition continued until the Mexican Revolution. In 1913, Alvaro Obregon took control of the port, and the war devastated the area economically. Many of the businesspeople had sided with Porfirio Díaz and had to leave. The city wanted to keep the annual Carnival tradition. Various social clubs vied for control over the event, especially the naming of the Carnival Queen. The queen was determined by which group provided the most money for Carnival events, which led to widespread cheating and scandals, especially in the year 1927, when the military had to get involved to keep order.
The goal of the fundraising was to decorate the 13 de Julio Plaza, as the event had become public. People came to the plaza dressed in costumes, and the event drew people from neighboring cities. The event still had the yearly parades, now with floats, and both private and public balls. Masks hiding identity were permitted, allow for the playing of practical jokes, and homosexuals were among those who took advantage of the anonymity.
By the 1960s and 1970s, the Carnival had evolved into an entirely popular event with mass participation, bringing in many visitors to the city. Sister cities such as El Segundo, California and Mesa, Arizona were invited to participate. After the inauguration of the Plaza de los Tres Presidentes, the event was moved to this larger plaza, which allowed for carnival rides and concerts by regionally and nationally known artists. The use of masks was banned due to violence. The traditional queen is now popularly elected, and the King is named the Rey Feo (Ugly King). Over time, the new plaza was no longer large enough to hold the event, and an admission charge was instituted. Security was instituted as well as checkpoints for weapons. The coronation of a Gay King was begun, and the number of floats participating in the parade grew.
As municipal seat, the city of Guaymas is the governing authority for more than 1,500 other communities, the most populous of which are Bahía San Carlos, Pueblo Vicam, San Ignacio Río Muerto, Pótam, Bahía de los Lobos and Ortíz. The municipality has a territory of 12,206.18km2. and a total population of 134,153, of which 101,502 or about 75% of which lives in the city proper. The municipality borders the municipalities of La Colorada, Suaqui Grande, Cajeme, Bácum and Hermosillo, with the Gulf of California to the west. Most of the municipality is flat and borders the Gulf of California with 175 km of coastline. Along its coast, there are important bays such as Guaymas, Lobos, San Carlos and La Herradura with 83% of Sonora’s piers in this municipality. Major elevations include the Serranías del Bacarete, Santa Ursula, San José, San Pedro, Luis Bland and the Cerros del Vigia. There are two main rivers called the Mátape and the Bácum which empty into estuaries on the Gulf. The municipality has a hot, dry climate with maximum temperatures averaging 31C and minimum temperatures averaging 18C. Maximum temperatures can reach 50C during the summers and from June to October ocean temperatures are in the 80sF. Most of the territory is covered with mesquite trees and cactus. It is also the home of the endangered California Fan Palm, and Washingtonia filifera is found in coastal groves. Other species such as Perityle have been long noted at Guaymas. Desert animals such as the desert tortoise, chameleon, puma, rattlesnakes and others are the main wildlife.
Almost all agriculture here is irrigated, depending on wells and the Ignacio Alatorre Dam located in the Guaymas Valley. Fields here yield wheat, soybeans, safflower, corn, cotton with some fruit trees. The most important livestock here is cattle, with goats coming second. However, cattle production has decreased somewhat, with pig and domestic fowl increasing. The most important industry is related to processing fish products, such as canning and freezing, all located in the city proper. A relatively large number of manufacturing operations controlled by foreign companies maquiladoras have opened here employing over 11,000, producing precision machined components for aerospace engines, electrical and mechanical components for automobiles, medical devices, and plastic injection molding for a variety of industries. Construction related to the port is also a major employer. Some mining occurs here, mostly graphite, with some small quantities of gold, silver and lead. The most important economic activity in the municipality is fishing. Most fish the waters of the Gulf but some are involved in aquaculture. Species sold include sardines, shrimp, and squid. In rural parts of Guaymas’ coast, fishing employs over 80% of the population.
The municipality, especially San Carlos, is popular with visitors from Arizona and Sonora but much of the coastal area, where the stark desert landscape meets the calm waters of the Gulf of California, is still undeveloped. San Carlos is an important destination for sportfishing with modern piers and 800 species that can be caught including sailfish, marlin, yellowtail and others. This bay holds a fishing tournament each year in July called the Torneo de Pesca de San Carlos. San Carlos also has an aquarium dedicated to dolphins and sea lions, which perform shows. The most notable peak in San Carlos is called the Tetacawi or Teta de Cabra, which appears to have two horns. Teta de Cabra means “goat’s udder” which it is supposed to resemble. Other sports that can be practiced here include kayaking, sailing, jetskiing, snorkeling, scuba diving, mountain biking and hiking. San Pedro Island off the coast is popular for snorkeling, scubadiving and visiting the sea lions that live there. The Bacochibambo or Miramar Bay also attracts some tourism. In this bay there is a pearl growing facility, the only one of its kind in the Americas. Pearls from here come in a range of colors such as grey, gold, bronze, olive green, black and pink.
On land, there is the Sahuaral Desert, about twenty minutes from the city of Guaymas. It contains a very tall cactus that is approximately 500 years old. Here, the Barajitas Canyon is also a natural reserve, with three ecosystems and considered a sacred place by the Seri Indians. The canyon is accessible only by boat.
The Guaymas-Empalme station for space observations is about six miles east of Empalme, Sonora, adjacent to Mexican Federal Highway No. 15. It is operated by the Mexican Space Agency. As a major link in the NASA's worldwide Manned Space Flight Network, the Guaymas Tracking Station, built in 1961, played a key role in tracking American manned space flights in the Mercury, Gemini, and Apollo programs through Apollo 13. The U.S. discontinued its use on November 30, 1970 due to changes in the Apollo mission profile which no longer required the Guaymas station. Equipment designed especially for support of the Apollo program was removed, but other equipment was left for support of Mexican space activities and future programs of mutual interest to Mexican scientists and NASA.El Segundo, California
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