According to the United States Census Bureau, the town has a total area of 11.5 square miles (29.8 km²), all of it land.
According to the Maricopa Association of Governments Municipal Planning Areas and Incorporated Areas Map PDF, the municipal planning area for Wickenburg includes a much larger area of land than any other planning area in the Phoenix metro area. If the city were to annex the entire area within its planning area, it would become the largest city by area in Arizona, surpassing Phoenix.
-Wikipedia