Thousands of fans, many snapping photographs, turned out to watch the start of demolition, expected to take about 60 days just to level and remove the south end of the stands.
The concrete stadium is being replaced by a new $400 million stadium that developers say should be ready for Opening Day, April 10, 2006.
The Cardinals initially wanted to implode the old ballpark, but the wrecking ball was deemed safer, the St. Louis Post-Dispatch said.
Demolition of the stadium opened in 1966 is expected to be finished in June, a week before Major League Baseball's All-Star Game break.
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