From the Statue of Liberty to the Empire State and Chrysler Buildings,
the Big Apple is reknown for its landmarks.
But while these structures give the city that never sleeps its identity, it is the bridges
spanning the city’s waterways that quite literally unite the five boroughs and keep
this vast metropolis moving.
Standing the test of time, shattering records and uniting millions, these are the iconic crossings of New York.
Starting at the entrance to New York Harbor and linking Staten Island to Brooklyn, the
Verrazzano-Narrows Bridge became the most recent of New York’s crossings to have held
the title of world's longest bridge when it first opened in 1964.
With a central span of 1,298 metres, the bridge was so long that its engineers had to rethink
its design in order to avoid the bridge tearing itself apart in strong winds.
As with any large object, bridges impede wind flow, creating turbulent vortices and regions
of varying pressure around the structure.
While this phenomenon creates a back and forth motion in vertical structures like skyscrapers,
for bridge decks the variations of high and low pressure cause the deck to oscillate up
and down, bending and flexing it to the point of collapse as was the case with the infamous
Tacoma Narrows bridge which collapsed due to high winds in 1940.
While single-deck bridges can overcome this by creating a more streamlined profile that
channels winds over and under the structure, the same method can’t be used for double
deck bridges like the Verrazzano-Narrows as the turbulence created between the decks further
amplifies the phenomenon and would create dangerous conditions for drivers.
We've used SimScale to simulate how wind passes around the structure with areas of high wind
speed shown in red.
To address this challenge, engineers devised a system of rigid steel lattice structures
that stiffened the deck, allowing wind to pass through the open roadway and making the
bridge capable of resisting even the strongest Atlantic storms.
With more than 150,000 users worldwide, SimScale is an easy-to-use cloud-based engineering
simulation platform that enables everyone to create powerful, high-fidelity simulations
in a web browser.
The platform can be tried for free through the Community account, which gives access
to thousands of public simulations to promote knowledge sharing and to crowdsource advice.
Despite the UK’s Humber Bridge overtaking it as the world's longest in 1981, Verrazzano-Narrows
remains the longest bridge in the Americas to this day.
Arguably the most famous New York crossing of all, the Brooklyn Bridge is one of three
suspension structures - along with the Manhattan and Williamsburg bridges - that cross the
East River to connect Manhattan with Brooklyn.
When it was completed in 1883, the Brooklyn Bridge was the longest bridge in the world
and provided the first permanent crossing between New York’s commercial centre in
Lower Manhattan and the bulk of the city’s 19th century workforce.
While often referred to as a suspension bridge, it is in fact a hybrid structure, utilising
elements of both suspension and cable-stayed bridge design.
Standing 85 metres high, the Brooklyn Bridge’s gothic inspired granite towers were the defining
feature of the city when the crossing first opened, dominating the skyline until the advent
of the skyscraper.
Now consisting of a pair of cable-stayed bridges, the original Kosciuszko Bridge was constructed
in 1939 to connect Brooklyn and Queens over Newton Creek.
Designed to carry 10,000 vehicles each day when it first opened, the decision to replace
the ageing structure was made in 2009 when the bridge was carrying 18 times its intended capacity.
In 2014, works began to construct a new five-lane eastbound bridge adjacent to the existing structure.
In order to construct the westbound bridge the original Kosciuszko Bridge was destroyed
in a controlled demolition on October 2017, the first time such a method was used on a
bridge in New York City.
The eastbound bridge carried traffic in both directions during the construction of its
westbound counterpart, before both bridges opening in their intended directions in August 2019
Linking Manhattan and the borough of Queens, the aptly named Queensboro Bridge was officially
renamed in 2011 to commemorate a former New York City Mayor, becoming the Ed Koch Queensboro Bridge.
Of the four major structures that cross the East River, the Queensboro Bridge is the only
one to deviate from the suspension model opting for a cantilever design to carry its double-deck
roadway.
With construction works first commencing in 1901, the bridge took until 1909 to complete
due to a series of delays brought about by labour disruptions and the partial collapse
of one of the cantilevered spans.
While construction accidents during the early 20th century were common by today's standards,
the collapse of the Queensboro Bridge was the result of a storm rather than human error.
Built in 1917, the Hell Gate Bridge is the longest of the three bridges that form the
Hell Gate Railroad Viaduct running through Queens and The Bronx.
While it was intended to operate as a four-track freight and passenger crossing, one of its
freight tracks was abandoned in the 1970’s and it is now used predominantly for passenger
services, forming part of Amtrak’s Northeast Corridor linking Boston with Washington DC.
Though relatively small in scale, the Hell Gate Bridge’s design proved so iconic that
it became the inspiration for one of the world's most recognisable structures,
the Sydney Harbour Bridge in Australia.
Named after the first US President, the George Washington Bridge is the only structure in
New York City to cross the Hudson River, with all other crossings from Manhattan to New
Jersey running through tunnels or via ferry.
Opened in 1931 the 1,450 metre suspension structures held the title of the world's longest
bridge until it was surpassed by the Golden Gate Bridge in 1937.
Designed by Cass Gilbert, the architect behind the city’s iconic Woolworth Building, the
bridge’s original design called for its towers to be clad in granite.
However, due to shifts in design trends and as a cost saving measure, these plans were
dropped leaving the robust steel lattice that was designed to carry the extra intended weight
as the bridge’s defining feature of the bridge.
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