You're standing across from one of three brownstones that J.P. Morgan owned on this block. Next to it is the addition to the Morgan Library designed by Renzo Piano in 2006. Around the corner is Morgan's original library, built in 1912.

The photographer Edward Steichen once said that looking into Morgan's "black eyes was like confronting the headlights of an express train bearing down on you." That unrelenting ambition drove his art acquisition as much as it had his business strategy. In 1901, he formed the country's first billion-dollar company- U.S. Steel- and following the Panics of 1893 and 1907 helped to save the country and then the city from financial ruin.

It was not until Morgan was in his 50s-after amassing his great wealth- that he turned buying art, rare books, and manuscripts into a second job. In 1901, one of Morgan's partner wrote: "We never see him and it is difficult to get hold of him. He spends his time lunching with Kings or Kaisers or buying Raphaels."

By 1890, more than 50% of Morgan's money went towards art, and by 1912, he had put $60 million (more than $1.5 billion today) into objects that ranged widely beyond Old Masters. There were Gutenberg Bibles, Roman frescoes, Assyrian reliefs, 17th century, German metalwork, tapestries, ivories, enamels, and furniture.

Morgan hired Charles McKim, of the architectural firm McKim, Mead, and White, to build him a library in which to put it all.

The design was inspired by Rome's 16th-century palaces and churches. Once inside the bronze doors, visitors entered a rotunda with a vaulted ceiling covered in scenes inspired by Raphael's ceiling the Vatican.

One of the three rooms you can visit today is Morgan's private study. This room- with its 16th-century Italian wood ceiling, red damask walls, stained glass window panels, and oversized glass window panels, and oversized Italianate desk became a haven for Morgan in the last years of his life. And when he died, in 1913, it was here that the family held the viewing. Morgan's son, Jack, turned his father's library into a public institution.