Anchorage, Alaska is 22 times larger than Boise, Idaho.
Area: 4,476 km2 calculated
Anchorage is a unified home rule municipality in the southcentral part of the U.S. state of Alaska. It is the northernmost city in the United States with more than 100,000 residents and the largest community in North America north of the 60th parallel. Wikipedia
Area: 207 km2 calculated
Boise is the capital and most populous city of the U.S. state of Idaho, as well as the county seat of Ada County. Located on the Boise River in southwestern Idaho, the population of Boise at the 2010 Census was 205,671, the 99th largest in the nation. Its estimated population in 2013 was 214,237. Wikipedia