Corydon, IA has a population of 1,544 and is the 12,509th largest city in the United States. The population density is 1,108 per sq mi which is 1929% higher than the Iowa average and 1123% higher than the national average. The median age in Corydon is 51 which is approximately 34% higher than the Iowa average of 38. In Corydon, 65% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 80% of Corydon residents were born in Iowa, 19% were born out of state, 0% were born outside of the United States and 1% were foreign born.