Name a major U.S. city located in the Southwest region of the country.
One major U.S. city located in the Southwest region of the country is Phoenix, Arizona.
Complete the following task based on the instruction and optional input provided.### Instruction:
Name a major U.S. city located in the Southwest region of the country.

### Output:
One major U.S. city located in the Southwest region of the country is Phoenix, Arizona.