- "Roswell was a sleepy cowboy settlement in postwar America, full of farmers and military men, until, one day, something extraordinary happened. Or so the legend goes. Ever since, UFO enthusiasts have flooded in, searching for some cosmic phenomenon to prove we're not all alone in the universe."
Roswell is notable for the 1947 UFO Crash. The United States Air Force covered up the alien crash, but conspiracy theories that aliens exist remain prevalent. Roswell has become a tourist trap for alien enthusiasts, with many alien-themed businesses catering to tourists.
Anti-immigrant sentiment, racism, and the threat of deportation are present from the start of the series. Being in New Mexico, it is near the United States border with Mexico, and ICE and border patrol are active in the area. The mayor has been pushing an anti-immigrant agenda.
In 2008, Rosa Ortecho allegedly got into a car accident, killing herself and two other people. This accident "tore this town in half," according to Sheriff Valenti. The event stoked anti-immigrant and racist sentiment, with some locals believing that if Rosa's family hadn't come here illegally that the two girls who died with her would still be alive. Following the accident, the Crashdown Cafe has been terrorized because it is owned by Rosa's family. Every year on the anniversary of Rosa and the girls' deaths, someone vandalizes the cafe.
- Crashdown Cafe, an alien-themed diner owned by Liz Ortecho's father Arturo Ortecho
- Grant Green's UFO Emporium, an alien-themed museum
- The Wild Pony, a locals bar run by Maria DeLuca
- Sanders' Auto, a service garage where Michael Guerin works and keeps an alien artifact bunker
- Chaves County Law Partners, where Noah Bracken works
- Drive-in movie theater
- Bean Me Up, an alien-themed coffee shop
- Roswell Community Medical, the hospital where Kyle Valenti and Liz Ortecho work
- Chaves County Sheriff's Department, the town's local law enforcement, where Max Evans works
- New Roswell High School, where most of the main cast attended high school
- United States Air Force Base, where Project Shepherd is located
- Frontier Valley Cemetery, Liz visits on the anniversary of Rosa's death
- Church, Liz visits on the anniversary of Rosa's death
- Max Evans' home, located in a more remote area outside the town
- Valenti hunting cabin, previously owned by Jim Valenti and passed to Alex Manes after his death
- Foster Homestead Ranch, site of the 1947 UFO Crash, where Michael works until the Air Force acquires the land
- The Turquoise Mines, where the pods are located