NYC Transit Employees at a Coney Island facility keep subway cars in working order. Flickr / MTAPhotos The New York subway system is celebrating its 110th birthday this month.

When you get right down to it, everyone basically loves the subway. It has moved millions for more than a century.

But celebrations aside, when it comes to New York's subway system, New Yorkers — being New Yorkers — have often had plenty to gripe about.

For example, the Metropolitan Transportation Authority (MTA) closed a major tunnel for more than a year to make repairs after Hurricane Sandy hit in 2012.

But problems like that obscure the fact that most of the time the trains run just fine.

It wasn't always this way. In 1984, trains averaged just 9,000 miles traveled between mechanical failures.

That's about when the MTA began putting real work into keeping trains running. Now, the MTA's Scheduled Maintenance System has the agency fixing aging components before they fail, improving that number to 160,000 miles.

That's thanks to the NYC Transit employees who work at facilities in Coney Island, repairing, replacing, and rebuilding the key components that keep the 40-ton subway cars in working order.

[An earlier version of this article was written by Alex Davies.]