from https://www.space.com/16657-worlds-first-commercial-airline-the-greatest-moments-in-flight.html

On Jan. 1, 1914, the world’s first scheduled passenger airline service took off, operating between St. Petersburg and Tampa, Fla. The St. Petersburg-Tampa Airboat Line was a short-lived endeavor — only four months — but it paved the way for today’s daily transcontinental flights.

The first flight’s pilot was Tony Jannus, an experienced test pilot and barnstormer. The first paying passenger was Abaram C. Pheil, former mayor of St. Petersburg. Their 21-mile (34-kilometer) flight across the bay to Tampa took 23 minutes. They flew in a “flying boat” designed by Thomas Benoist (pronounced ben-wah), an aviation entrepreneur from St. Louis.