1653: Dutch settlers put up a 12-foot high wooden barrier across the lower end of Manhattan to protect them from attacks by native Americans and the British.
1685: Wall Street is laid out along the line of the stockade.
1792: Twenty-four brokers and merchants sign the Buttonwood Agreement, agreeing to trade securities for commission. The pact was named for a Buttonwood tree that was their informal meeting place.
1817: A formal organization is formed among brokers called the New York Stock & Exchange Board, renting rooms on 40 Wall Street.
1863: The New York Stock & Exchange Board changes its name to the New York Stock Exchange.
1867: The stock "ticker" is invented, revolutionizing the market by allowing investors to get current stock prices anywhere.
1878: The first telephone is installed on the floor of the exchange, two years after Alexander Graham Bell's successful tests of the new technology.
1903: The NYSE moves to a new building at the corner of Broad Street and Wall Street, where it is still housed today.
1914: As World War I escalated, the NYSE closed for over four months to stop plunging stock prices. It was the longest period the NYSE has been closed.
1929: Stocks fall dramatically on October 24, which became known as "Black Thursday" and is also considered the start of the Great Depression.
1943: Women work on the floor of the NYSE for the first time.
1954: The Dow Jones industrial average surpasses its 1929 peak for the first time.
1987: The Dow Jones industrial average falls 22.61 percent, the largest one-day percentage drop.
2001: The NYSE closes for four days after the terrorist attacks on the World Trade Center. When it reopened, the Dow fell 684.81 points, its steepest point decline in a day.
2006: The NYSE merges with electronic trading exchange Archipelago holdings creating the NYSE Group. Inc., a publicly traded company.
2007: NYSE Group Inc. merges with European stock exchange operator Euronext N.V., forming NYSE Euronext Inc.
2008: NYSE Euronext Inc. acquires the American Stock Exchange.
2011: NYSE Euronext Inc. agrees to merge with Germany's Deutsche Boerse AG, owner of the Frankfurt stock exchange. The deal would give Deutsche Boerse shareholders 60 percent ownership of the new company, which hasn't been named yet. Shareholders and regulators must still sign off on the deal.
Sources: NYSE website, AP research.