OMG: Seeing Is Believing In US Today

Nearly a century after the Second Avenue subway was first proposed, part of the line is finally scheduled to open in December.

“Seeing is believing,” one Upper East Side resident said. “It’s been a long haul.”

And a heavy one.

Over the past decade, as you were going about your merry days, seven colossal machines have been devouring the city bedrock beneath your feet to make way for the new line and two other transit projects.

These giants, called tunnel-boring machines, are anything but boring.

The hulking Adi, a machine that mined almost 15,000 feet from 92nd Street to 63rd Street at a rate of 50 feet per day, weighs 485 tons, with a 200-ton cutting head.

Georgina and Emma churned beneath 11th Avenue.

Tess and Molina, under Queens.

And don’t forget Robbins and Seli, who gnashed another 32,000 feet of Manhattan’s underbelly.

They’re not as cute as their names.

The mechanical monsters have sharp, tungsten carbide shears in front, and in back, equipment the length of a few city blocks.

The construction work for the line did spur complaints over loud explosions. What was the wonderful result of all that tunneling in recent years, as described by the M.T.A.?

“13 miles of new tunnels through the mica-inflected granite schist that anchors the skyscrapers of Midtown.”

You can learn more about the Second Avenue subway from Emma G. Fitzsimmons, a transit reporter for The New York Times, by tuning into a Facebook Live chat at 10 a.m.