Zaria is 3.6 times larger than Hayward, California.
Area: 117 km2 calculated
Hayward is a city located in Alameda County, California in the East Bay subregion of the San Francisco Bay Area. With a population in 2014 of 149,392 Hayward is the sixth largest city in the Bay Area and the third largest in Alameda County. Wikipedia
Area: 426 km2 calculated
Zaria is a major city in Kaduna State in Northern Nigeria, as well as being a Local Government Area. Formerly known as Zazzau, it was one of the original seven Hausa city-states. The 2006 Census population was 408,198. The current Emir of Zazzau is Shehu Idris. Wikipedia