It's about sixteen-and-a-half times as big as Butte.
In other words, 31,000,000 dunams is 16.696950 times the size of Butte, and the size of Butte is 0.05989118 times that amount.(The City and County of Butte-Silver Bow) (Montana)
The eighth-largest city in the country and the second-largest in Montana, the Butte-Silver Bow City County measures 1,856,627 dunams. The city was called "the Richest Hill on Earth" for its numerous copper, silver, and gold mines.
It's about nineteen times as big as Oklahoma City.
In other words, 31,000,000 dunams is 19.211270 times the size of Oklahoma City, and the size of Oklahoma City is 0.05205278 times that amount.(a.k.a. OK City, a.k.a. OKC) (Oklahoma)
The capital and largest city in the state, Oklahoma City measures 1,613,636 dunams. The city is known for its energy exploration and information technology industries and as the location of the 1995 bombing of the Murrah Federal Building by Timothy McVeigh.
It's about twenty times as big as Oahu.
In other words, 31,000,000 dunams is 20.061 times the size of Oahu, and the size of Oahu is 0.049848 times that amount.(a.k.a. O`ahu, a.k.a. The Gathering Place) (Hawaii)
The third-largest of the Hawaiian Islands, Oahu measures 1,545,300 dunams in total area. It is known as the home of the state capital, Honolulu, as the site of the 1941 attack on Pearl Harbor, and as the filming location of numerous movies and television shows.
It's about twenty-and-a-half times as big as Houston.
In other words, 31,000,000 dunams is 20.650 times the size of Houston, and the size of Houston is 0.04843 times that amount.(Texas)
The largest city in Texas and the fourth-largest city in the United States as of 2009, Houston measures 1,501,000 dunams in total area. The city is known for its broad corporate base, prominence in oilfield equipment, and for its port, which accepts more cargo than any other port in the United States.
It's about twenty times as big as Kaua'i.
In other words, 31,000,000 dunams is 21.6720 times the size of Kaua'i, and the size of Kaua'i is 0.046142 times that amount.(a.k.a. Kauai, a.k.a. The Garden Isle, a.k.a. Taua'i) (Hawaii)
The fourth-largest of the Hawaiian Islands, Kaua'I measures 1,430,400 dunams in total area. It is known as the home of Nā Pali Coast State Park.
It's about one-twentieth as big as Texas.
In other words, 31,000,000 dunams is 0.044564489 times the size of Texas, and the size of Texas is 22.4393910 times that amount.(United States)
The "Lone Star State," Texas measures 695,621,130 dunams in total area. Texas covers so much area that Texarkana — a city in the state's northeastern corner — is about 30 km closer to Chicago, Illinois, than it is to El Paso — in the western corner of Texas.
It's about thirty times as big as Phoenix.
In other words, 31,000,000 dunams is 25.20 times the size of Phoenix, and the size of Phoenix is 0.0397 times that amount.(Arizona)
The capital of and largest city in Arizona and fifth-largest city in the United States as of 2009, Phoenix measures 1,230,000 dunams in total area. The city is known as an economic and cultural center of the American Southwest.