Southwest Airlines celebrated the 50th anniversary of their partnership with the Valley International Airport in Harlingen on Tuesday.

The airline flies more than half a million people in and out of that airport every year.

Marv Esterly, the airport’s director of aviation, said the airline brings an estimated economic impact of $200 million per year to the region.

Houston, San Antonio, Dallas and now Harlingen are the Texas cities who have celebrated 50 years of service with Southwest Airlines.