The Rochester airport saw its busiest year ever in 2018 after an expansion, the addition of a third major airline and the launch of a program that encourages local business travelers to use the airport rather than drive 90 minutes to the larger Twin Cities terminals.

The airport's total passenger count, at 366,542 people flying in and out, surpassed the previous record of 344,556 set in 1977 and was a 26 percent bump over 2017, the airport reported.

"We are incredibly grateful for the increased support," said John Reed, RST's executive director. He said the airport traffic makes a strong case for the city to get service to a western hub such as Dallas or Denver.

"The airport cannot recruit that service alone. It takes local travelers filling the planes now to bring more service to our region," he said.

The ramp-up follows a general quickening of the Rochester economy in recent years as the Mayo Clinic's expansion project, known as Destination Medical Center, enters its sixth year. The massive $5.6 billion, 20-year plan promises to grow the Mayo campus and downtown Rochester and add thousands of new employees to the world-renowned hospital.

Three major airlines either launched or expanded their service to and from Rochester in the summer of 2017. Delta Air Lines added a fourth daily flight to Minneapolis-St. Paul, with a return to Rochester, along with a second daily flight to and from Atlanta.

United Airlines launched Rochester service about the same time, with three flights daily to and from Chicago's O'Hare airport. American Airlines, with four daily flights to and from Chicago, started using larger planes for those flights, according to the airport.

A bid last summer from regional airline Elite Airways of Portland, Maine, to launch routes between RST and Arizona and Florida, where the Mayo Clinic has large hospitals, fell through. The airline cited low bookings for the failed launch of new service.

The airlines' expansion plans coincided with a decision by the Mayo Clinic to encourage its employees to use the Rochester airport.

Some 70 businesses had already pledged to join the "Fly RST" effort when the Mayo Clinic said it would also join. A renovation and expansion of the airport's customs area and consolidation of the ticketing and baggage claim area was completed last year.

Twitter: @_mattmckinney