Omaha, Nebraska is 3.2 times larger than Fontana, California.
Area: 106 km2 calculated
Fontana is a city of 200,762 residents in San Bernardino County, California. Founded by Azariel Blanchard Miller in 1913, it remained essentially rural until World War II, when entrepreneur Henry J. Kaiser built a large steel mill in the area. Wikipedia
Area: 342 km2 calculated
Omaha is the largest city in the state of Nebraska, United States, and is the county seat of Douglas County. It is located in the Midwestern United States on the Missouri River, about 10 miles north of the mouth of the Platte River. Wikipedia