At 8:30 p.m. on 16 May 1916, John J. Carty banged his gavel at the Engineering Societies Building in New York City to call to order a meeting of the American Institute of Electrical Engineers. This was no ordinary gathering. The AIEE had decided to conduct a live national meeting connecting more than 5,000 attendees in eight cities across four time zones. IEEE Spectrum recounts this occasion.

More than a century before Zoom made virtual meetings a pedestrian experience, telephone lines linked auditoriums from coast to coast. AIEE members and guests in Atlanta, Boston, Chicago, Denver, New York, Philadelphia, Salt Lake City, and San Francisco had telephone receivers at their seats so they could listen in.

The AIEE, a predecessor to the IEEE, orchestrated this event to commemorate recent achievements in communications, transportation, light, and power. The meeting was a triumph of engineering, covered in newspapers in many of the host cities. The Atlanta Constitution heralded it as “a feat never before accomplished in the history of the world.” According to the Philadelphia Evening Ledger, the telephone connections involved traversed about 6,500 kilometers (about 4,000 miles) across 20 states, held up by more than 150,000 poles running through 5,000 switches. It’s worth noting that the first transcontinental phone call had been achieved only a year earlier.

Read more in the article here. Via Waxy.