Established as Sun Valley Airlines (Boise, ID) which merged with Key Airlines in 1964 and operated as Sun Valley Key Airlines in the early 1970's. Renamed Key Airlines in the mid-1980's. Key Air was purchased by Presidential Airways in 1986 and then one year later by World Airways but in both instances continued to fly under its own colors. Sold by World Airways in 1992. Chapter 11 bankruptcy followed shortly thereafter. The airline restarted in 1993 as Key International Airlines. Adopted National Airlines Sun King logo in early 1993 but went bankrupt again in May, 1993 and was liquidated.