The first transcontinental phone call is made in the U.S.

On January 25, 1915, Alexander Graham Bell sat in New York and spoke to his old assistant Thomas Watson in San Francisco, completing the first transcontinental telephone call in the United States. Nearly four decades earlier the two had made the very first phone call across a single room; now their voices crossed an entire continent.

The ceremonial call linked multiple participants, including AT&T president Theodore Vail from Georgia and President Woodrow Wilson at the White House. To mark the occasion, Bell repeated his famous original line, “Mr. Watson, come here, I want you.” Watson, separated by thousands of miles, replied that it would now take him a week.

The connection ran on a coast-to-coast line strung from tens of thousands of poles.

The feat was possible thanks to newly developed vacuum-tube repeaters that boosted the signal across the distance. It turned a regional novelty into a national network, knitting the country together one conversation at a time.