A big chunk of an old New York bridge went down in history Tuesday as explosives demolished the eastern part of the Tappan Zee Bridge.

The bridge has been replaced by the Governor Mario M. Cuomo Bridge, which carries Interstate 87 traffic over the Hudson River about 30 miles north of New York City.

The Tappan Zee, which opened in 1955, was a poster child for America’s crumbling bridges and roads. Governor Andrew M. Cuomo, the son of the new bridge’s namesake, recalled in 2017 an experience familiar to many Tappan Zee drivers — steel plates that shifted beneath traffic, providing unnerving glimpses through road cracks of the river far below.

“I think it traumatized an entire generation,” he said.

The original demolition plans were to avoid the use of explosives that could have an impact on fish habitats. But experts determined the span was structurally unsound, preventing workers from continuing to take it down piece by piece.

There are plans to dismantle the western portion without explosives sometime this year.