An iconic Hudson Valley structure is no longer as crews brought down the old Tappan Zee Bridge Tuesday.

The demolition was expected to take place between 10 a.m. and 10:30 a.m., but was delayed until 10:52 a.m.

The reason explosives were used is because engineers determined the structure was unsound and declared it off-limits to workers. In September 2017, officials had to postpone the opening of the second span of the new bridge after crews heard popping sounds coming from the old bridge.

Now that the bridge it down, the steel will be recovered by Marine salvage teams using chains that have been laid on the riverbed. They'll use the chains to lift up the steel and haul it out by barge.