The Dow Jones Industrial Average fell more than 830 points, underlining an unraveling of the main U.S. stock markets on Wednesday as rates climbed. The Dow DJIA, +0.19% finished off 832 points, or 3.2%, at 25,598 and notched its ugliest day since Feb. 8, as Wall Street investors reacted to a rising-rate environment that has seen the 10-year Treasury note TMUBMUSD10Y, 0.669% yield 3.22%--its highest level since 2011. The S&P 500 index SPX, +0.29% closed down 3.2% at 2,785, also its worst session in 8 months. Meanwhile, the Nasdaq Composite Index COMP, +0.36% tumbled by the most among its equity peers. It dropped 4.1% at 7,422 and registered its worst day since June 24 of 2016. The index also tumbled below its 200-day moving average, viewed by technical analysts as a gauge of bullish and bearish momentum in an asset.