Lower Manhattan is the southernmost part of the island of Manhattan, the main island and center of business and government of the City of New York. Lower Manhattan or "downtown" is defined most commonly as the area delineated on the north by 14th Street, on the west by the Hudson River, on the east by the East River, and on the south by New York Harbor (also known as Upper New York Bay). When referring specifically to the lower Manhattan business district and its immediate environs, the northern border is commonly designated by thoroughfares approximately a mile-and-a-half south of 14th Street and a mile north of the island's southern tip: Chambers Street from near the Hudson east to the Brooklyn Bridge entrances and overpass. Two other major arteries are also sometimes identified as the northern border of "lower" or "downtown Manhattan": Canal Street, roughly half a mile north of Chambers Street, and 23rd Street, roughly half a mile north of 14th Street. Anchored by Wall Street, in Lower Manhattan, New York City functions as the financial capital of the world and is home to the New York Stock Exchange, the world's largest stock exchange by market capitalization of its listed companies.