The 1929 Wall Street Crash reached its largest one-day share-volume peak, known as Black Tuesday, on October 29, 1929.
Black Tuesday followed Black Thursday on October 24 and Black Monday on October 28. On October 29, investors traded about 16 million shares on the New York Stock Exchange, a record that stood for decades. Prices fell sharply as confidence in heavily leveraged stocks collapsed.
The crash did not single-handedly cause the Great Depression, but it intensified a broader economic downturn. Bank failures, falling industrial production, debt problems, and reduced consumer spending also played major roles.
A common mix-up is treating Black Tuesday as the entire crash. The Wall Street collapse unfolded across several trading sessions in October 1929, after stock prices had already declined from their September peak.