Bernalillo County, NM
Bernalillo County was founded in 1852. The largest city within its boundaries is Albuquerque. Albuquerque is the county seat as well as the highest metropolitan city in the U.S., sitting at an elevation of 5,314 feet above sea level. The area is also known as the Hot Air Balloon Capital of the world. As of 2018, the population was estimated at 678,701 - making Bernalillo the most populous county in the state of New Mexico.
Doña Ana County, NM
Doña Ana County is the second most populous county in the state with an estimated population of 217,522. The county was founded in 1852 and is located in the southern portion of the state. The largest city within its boundaries is Las Cruces. The area is also home to the Organ Mountains, the White Sands Missile Range, and an agricultural region on the floodplain of the Rio Grande.
Sandoval County, NM
Sandoval County was established in 1903 and named for a prominent family in the area. The county is the fourth most populous county in the state of New Mexico and has a population of 145,179. The Mormon Battalion Monument, a significant landmark in Sandoval, was removed in 1982 and then rebuilt in 1996. The county has the second highest number of Native American reservations in the U.S., with twelve reservations total and two join-use areas.
San Juan County, NM
Established in 1887, San Juan County has an estimated population of 125,043 people. It is the fifth most populous county in New Mexico, and home to one of the four portions of the Four Corners Monument. The U.S. government owns only 29 percent of the county, while the other 60 percent is owned by the Navajo Nation.
Santa Fe County, NM
Santa Fe County was founded in 1852. With 150,056 residents, it is the third most populated county in the state. Within its boundaries is the oldest church in the United States, the San Miguel Chapel, built between 1610-1626. Santa Fe County is also home to the state capital, Santa Fe: a city known for its art culture and recognized as a part of UNESCO’s Creative Cities Network.