The “Twin Towers” of the World Trade Center officially opened in
New York City after years of delays. The buildings replaced the
Empire State Building as the world’s tallest building. Though they
would only hold that title for a year, they remained a dominant
feature of the city’s skyline and were recognizable the world over
long before they were destroyed in a terrorist attack in 2001. 

Manhattan in 1973.

Sept. 19, 2001: Smoke rises from ground zero of the
collapsed World Trade Center, more than a week after
the terrorist attacks in New York. (AP)

Today, the One World Trade Center in Lower Manhattan. A 
height of 1,776 feet includes its spire.

On April 3, 1860, the first Pony Express mail, traveling by horse
and rider relay teams, simultaneously left St. Joseph, Missouri,
and Sacramento, California. Ten days later, on April 13, the
westbound rider and mail packet completed the approximately
1,800-mile journey and arrived in Sacramento, beating the
eastbound packet’s arrival in St. Joseph by two days and setting
a new standard for speedy mail delivery.

On March 13, 1942, the Quartermaster Corps (QMC) of the United
States Army began training dogs for the newly established War
Dog Program, or “K-9 Corps.”

Well over a million dogs served on both sides during World War
I, carrying messages along the complex network of trenches and providing some measure of psychological comfort to the soldiers.

On March 11, 1989, "Cops," a documentary-style television
series that follows police officers and sheriff’s deputies as
they go about their jobs, debuts on Fox. "Cops" went on to
become one of the longest-running shows in television
history. It went off the air in 2020.

The show, which was created by John Langley and Malcolm
Barbour, was a pioneer in reality television.

When the cameras of “COPS” were in Portland, Oregon.

March 10, 1876, the first discernible speech was transmitted
over a telephone system when inventor Alexander Graham
Bell summoned his assistant in another room by saying,
“Mr. Watson, come here; I want you.” Bell had received a
comprehensive telephone patent just three days before.