Tulsa, Oklahoma is 2.2 times larger than Amarillo, Texas.
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
Area: 569 km2 calculated
Tulsa is the second-largest city in the U.S. state of Oklahoma and 46th-largest city in the United States. The population has grown since the 2010 census, With a population of 398,121 as of July 2013. Wikipedia