Denver is the “Mile High City” since its elevation is exactly one mile above sea level. But that’s not its only unique claim.
A group of Georgia prospectors found Colorado Territory on their expedition seeking gold. The gold rush is the main reason the city was developed. However, when a gold claim was discovered in a neighboring town, the gold seekers deserted the city.
Those disillusioned by the lack of gold and harsh winters elsewhere returned to Denver for its mild climate and to pursue other endeavors, building its reputation as a center for trade.