Amarillo, Texas is 4.3 times larger than Santa Maria, California.
Area: 60 km2 calculated
Santa Maria is a city on the Central Coast, in Santa Barbara County. It is approximately 120 miles northwest of Los Angeles. The 2012 population was 101,459, putting it ahead of Santa Barbara for the first time and making it the most populous city in the county. Wikipedia
Area: 257 km2 calculated
Amarillo is the fourteenth most populous city in the state of Texas, also the largest City in the Texas Panhandle, and the seat of Potter County. A portion of the city extends into Randall County. The population was 190,695 at the 2010 census. Wikipedia