Quick: Name the Largest Factory in New York City
It's venerable Steinway & Sons, now celebrating 150 years of carefully crafting grand pianos... the old-fashioned way. A recent profile in the March 17 issue of Fortune tells the story (with beautiful pictures illustrating the process of building a Steinway).

In March 1853, piano-maker Henry Steinway moved from Germany to Manhattan and started the company with his sons. Located across the East River in Astoria (Queens) since the 1880s, Steinway still creates instruments that are marvels of the world. The company's enormous 450,000 square foot plant produces between 2,000 and 3,000 instruments each year, ranging from its $17,000 uprights to its $50,000 grand pianos to its $500k-plus custom orders.

It takes at least nine months for each instrument to be born -- for each of its 12,000 parts to be crafted (mostly by hand!) and carefully assembled and adjusted by Steinway's international team of 500 artisans.

Henry Steinway himself would find the process very familiar, from the lamination & bending of the maple rim, to the planing and placement of the spruce soundboard, and the multi-step assembly of the action (the keyboard mechanism). However, Steinway has selectively modernized along the way, holding many patents for technical innovation, and of course no longer using real ivory for the keys.

Other fine instrument makers (including Yamaha and Kawai) sell more units, but Steinway still dominates sales to concert halls (over 95% of the market).

Link to the Steinway company site and online factory tour.

Link to the Fortune article (no pictures, unfortunately)