Petrified Forest National Park is 2.4 times larger than Portland, Oregon.
Area: 903 km2 calculated
Petrified Forest National Park is a United States national park in Navajo and Apache counties in northeastern Arizona. Named for its large deposits of petrified wood, the park covers about 146 square miles, encompassing semi-desert shrub steppe as well as highly eroded and colorful badlands. Wikipedia
Area: 376 km2 calculated
Portland is the largest city by population in the U.S. state of Oregon, near the confluence of the Willamette and Columbia rivers. Wikipedia