Few travelers ever could say Delta Air Lines hasn't been here for the long haul.

The largest-volume carrier serving Charleston International Airport will mark its 80th anniversary in the Lowcountry on Friday.

The Atlanta-based carrier started serving Charleston with mail service on July 7, 1934, five years after the airport opened. A month later, on Aug. 5, 1934, airline passenger service began, carrying seven ticketholders on a 100-mph Stinson T airplane.

It took 23 hours and 42 minutes with 10 stops to fly mail to Dallas.

The largest Delta aircraft today serving Charleston, an MD88, carries 149 passengers and travels up to 498 mph. It also has more competition than 80 years ago, including JetBlue, Southwest, US Airways and United.

When the current 10-gate terminal opened in 1985, Delta offered seven daily nonstop flights and transported 400 passengers a day to Atlanta from the North Charleston airport.

Today, the airline, which has since absorbed rival Northwest Airlines, offers 35 flights in and out of Charleston to Detroit, Atlanta and New York City's LaGuardia and JFK airports. It takes 45 to 90 minutes to get to those destinations.

Delta and its Delta Global Services, an aviation ground-handling service, employ about 100 people at Charleston International.

A reception will be held at 11 a.m. Friday near Delta's ticket counter, which will soon be moved across the aisle of part of the $189 million renovation and expansion of the airport.

Charleston International is adding five new gates, a third baggage carousel, consolidated security checkpoints and numerous other changes as passenger demand rises.

The airport saw 2.9 million passengers in 2013, a big leap from the first 70 who flew in all of 1931 on Eastern Air Transport, later Eastern Airlines, which is now defunct. The number of airport passengers at Charleston is expected to climb to nearly 4 million over the next decade or so.

Reach Warren L. Wise at 937-5524 or twitter.com/warrenlancewise.