Geography
Sonora covers 179,355 km², second only to Chihuahua, with 2,944,840 people — 18th by population but 30th by density. The state is a tilted plain: the Sierra Madre Occidental forms the eastern wall, reaching about 2,600 m in the Sierra Los Ajos and the ranges around Cananea, and the land falls west in a series of broad valleys to a low, hot coast on the Gulf of California.
Most of Sonora is Sonoran Desert, the only desert in the world where the saguaro cactus grows wild. In the north-west corner the Pinacate y Gran Desierto de Altar reserve, listed by UNESCO in 2013, combines a field of black volcanic craters with the largest active dune sea in North America. The four rivers that cross the state — the Sonora, Yaqui, Mayo and Altar — are all dammed, and the water they store irrigates the Yaqui and Mayo valleys around Ciudad Obregón and Navojoa, the wheat belt where Norman Borlaug ran the breeding programme behind the Green Revolution. The extreme north-west touches the Colorado River delta at San Luis Río Colorado.
The coast runs about 1,200 km from the delta to the Sinaloa line, with Puerto Peñasco at the head of the gulf, San Carlos and Guaymas in the middle, and Bahía de Kino facing Isla Tiburón — at 1,201 km² the largest island in Mexico and the territory of the Comcaac (Seri). The Yaqui hold eight towns along the lower Yaqui River. Inland, Cananea works the largest copper mine in the country, and Sonora produces roughly four-fifths of Mexico's copper. Summers on the plain are among the hottest in Mexico, regularly above 45 °C in Hermosillo, and almost all the rain arrives with the July–September monsoon.
Main cities
| Municipality | Population (2020) | Note |
|---|---|---|
| Hermosillo | 936,263 | State capital; car assembly and services |
| Cajeme (Ciudad Obregón) | 433,000 | Yaqui Valley farming and agribusiness |
| Nogales | 264,782 | Border crossing to Arizona; maquiladoras |
| San Luis Río Colorado | 192,739 | Border crossing to Yuma, Arizona |
| Navojoa | 163,650 | Mayo Valley; gateway to Álamos |
| Guaymas | 156,863 | Main deep-water port; San Carlos resort |
| Agua Prieta | 91,929 | Border crossing to Douglas, Arizona |
| Caborca | 85,631 | Irrigated farming on Highway 2 |
| Puerto Peñasco | 62,177 | Beach resort, four hours from Phoenix |
Sonora is divided into 72 municipalities. Cajeme's figure is rounded; the rest are census counts for the whole municipality, which in Sonora is usually much larger than the built-up town.
Neighbouring states
Three states border Sonora: Chihuahua along the crest of the Sierra Madre Occidental to the east, Sinaloa to the south at the Fuerte and Mayo lowlands, and Baja California to the west, where the two meet across the lower Colorado River. The northern boundary is the international line — about 590 km facing Arizona and a short stretch of the New Mexico bootheel, with crossings at Nogales, Agua Prieta, San Luis Río Colorado, Sonoyta and Naco, all shown on the US–Mexico border map. Sonora is counted in Northern Mexico and its eastern edge belongs to the Sierra Madre.
Getting there
Hermosillo (HMO) is the main airport, with domestic routes and direct flights to several US cities. Ciudad Obregón (CEN), Nogales (NOG), Guaymas (GYM) and Puerto Peñasco (PPE) handle smaller traffic; the airports map lists them by code. Many US visitors simply fly to Tucson or Phoenix and drive across.
Federal Highway 15 and its toll twin 15D run the length of the state from the Nogales border through Hermosillo, Guaymas and Ciudad Obregón into Sinaloa — this is the main road corridor of the Pacific side of Mexico. Highway 2 follows the border west to Tijuana and east to Agua Prieta and Chihuahua; Highway 8 drops from Sonoyta to Puerto Peñasco; Highway 16 climbs east from Hermosillo over the sierra at Yécora to Chihuahua city. From Mexico City to Hermosillo is about 2,000 km and 21 hours of driving. See the road map and the physical map.
Questions about Sonora
Where is Sonora on the map of Mexico?
In the north-west, on the mainland side of the Gulf of California, directly south of Arizona. It borders Chihuahua, Sinaloa and Baja California, and it is the second-largest state in Mexico after Chihuahua.
Does Sonora change its clocks for daylight saving?
No. Sonora has stayed on UTC−7 all year since 1998, matching Arizona, which does not use daylight time either. That makes Sonora the same hour as Phoenix year-round, an hour behind California in winter and the same as California in summer. The time zones map shows the four zones.
What is the drive from Nogales to Hermosillo?
About 280 km on Federal Highway 15D, roughly three hours on a four-lane toll road. Continuing south, it is another 130 km to Guaymas and 250 km to Ciudad Obregón.
Is Sonora safe to visit?
Puerto Peñasco, Hermosillo, San Carlos and the Highway 15 corridor carry heavy US traffic, while the US State Department has advised against travel in parts of the state, particularly the sierra east of Highway 15 and some border areas at night. Check the current advisory and drive the toll roads by day.