I toured Amazon's massive, robot-powered warehouse that serves New York City - these are the 6 incredible little details that stood out

Ben Gilbert/Business Insider

The final stop on the way to delivery: an automated carousel that directs boxes to specific trucks.

• Amazon's first major warehouse in New York City opened last September in the borough of Staten Island.
• The massive "fulfillment center" could hold 18 football fields within its hundreds of thousands of square feet, and more than 3,000 people are employed there.
• I visited the facility last week for a tour, and was overwhelmed by all the incredible little details.
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You've no doubt heard as much before: Amazon's shipping warehouses, the so-called "fulfillment centers," are massive structures.

And while that aspect was certainly impressive, a recent tour of Amazon's first-ever New York City fulfillment center opened my eyes to the many other tiny details that enable the retail giant to deliver such a vast array of products at such a rapid clip.

From a ballet of robots to a brilliantly simple sorting system to a timeless technology, here are the most impressive and unexpected little details I saw inside the Amazon facility that services one of America's largest markets: New York City.