Boise, Idaho is 49% larger than Fort Collins, Colorado.
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
Area: 138 km2 calculated
Fort Collins is a Home Rule Municipality in and the county seat of Larimer County, Colorado, United States. Situated on the Cache La Poudre River along the Colorado Front Range, Fort Collins is located 65 miles north of the Colorado State Capitol in Denver. Wikipedia