The Metropolitan Museum of Art in New York City opened on February 20, 1872. It is the largest art museum in the United States, with 7.06 million visitors to its three locations in 2016. It is the third most visited art museum in the world and the fifth most visited museum of any kind.
In April, 1870, the New York State Legislature granted an Act of Incorporation
“for the purpose of establishing and maintaining in said City a Museum and Library of Art, of encouraging and developing the Study of the Fine Arts, and the application of Art to manufacture and natural life, of advancing the general knowledge of kindred subjects, and to that end of furnishing popular instruction and recreations”.
This legislation was supplemented later by the 1893 Act, Chapter 476, which required that its collections
“shall be kept open and accessible to the public free of all charge throughout the year.”
(Hmmmmm. I paid the last time I went.)
The founders included businessmen and financiers, as well as leading artists and thinkers of the day, who wanted to open a museum to bring art and art education to the American people.
Summarized from Wikipedia.