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NEW YORK (FOX 5 NEWS) - For the last four years, we've watched the new Tappan Zee Bridge being built, piece by piece like a giant puzzle. Several months before its planned opening, it is now possible to drive across the entire three-mile length of the new bridge.
However, that doesn't mean the bridge is ready for traffic. Several months still remain before four lanes officially open to vehicles traveling west from Westchester County to Rockland County.
More work still needs to be done. Crews need to add a layer of asphalt, install LED light poles and digital message boards, and put up fencing to deter jumpers.
Drivers told us they are impressed with the progress.
Westchester-bound traffic will have to use the existing bridge for a few extra months but then will share the new crossing with westbound vehicles while workers take apart the old bridge.
When a second parallel four-lane span opens in 2018, west- and eastbound traffic will each get its own span.
The original crossing opened in 1955.