Mount Aetna, MD has a population of 699 and is the 17,493rd largest city in the United States. The population density is 495 per sq mi which is 4% higher than the Maryland average and 446% higher than the national average. The median age in Mount Aetna is 40 which is approximately 5% higher than the Maryland average of 38. In Mount Aetna, 69% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 57% of Mount Aetna residents were born in Maryland, 42% were born out of state, 1% were born outside of the United States and 0% were foreign born.