Othmar Ammann was born near Schaffhausen, Switzerland, in 1879.
His father was a manufacturer and his mother was a hat maker.
He received his engineering education at the Polytechnikum in Zürich, Switzerland.
He studied with Swiss engineer Wilhelm Ritter.
In 1904, he emigrated to the United States, spending much of his career working in New York City.
He became a naturalized citizen in 1924.

In 1905 he briefly returned to Switzerland to marry Lilly Selma Wehrli.
Together they had three children –  Werner, George, and Margot – before she died in 1933.
He then married Klary Vogt Noetzli, herself recently widowed, in 1935 in California.

Ammann wrote two reports about bridge collapses, the collapse of the Quebec Bridge and the collapse of the original Tacoma Narrows Bridge (Galloping Gertie).
It was the report that he wrote about the failure of the Quebec Bridge in 1907 that first earned him recognition in the field of bridge design engineering.
Because of this report, he was able to obtain a position working for Gustav Lindenthal on the Hell Gate Bridge.
By 1925, he had been appointed bridge engineer to the Port of New York Authority.
His design for a bridge over the Hudson River was accepted over one developed by his mentor, Lindenthal. (
Lindenthal's "North River Bridge" designs show an enormous, 16+ lane bridge that would have accommodated pedestrians, freight trains, rapid transit, and automobile traffic.
The bridge, which would have entered Manhattan at 57th Street, was rejected in favor of Ammann's designs primarily due to cost reasons.)

Ultimately, this became the George Washington Bridge.
Under Ammann's direction, it was completed six months ahead of schedule for less than the original $60 million budget.
Ammann's designs for the George Washington Bridge, and, later, the Bayonne Bridge, caught the attention of master builder Robert Moses, who drafted Ammann into his service.
The last four of Ammann's six New York City bridges — Triborough, Bronx-Whitestone, Throgs Neck, and Verrazzano-Narrows Bridge were all built for Moses' Triborough Bridge and Tunnel Authority.
In 1946, Ammann and Charles Whitney founded the firm Ammann & Whitney.
In 1964, Ammann opened the Verrazzano-Narrows Bridge in New York, that had the world's longest suspended span of 4,260 feet (1,300 m), and was the world's heaviest suspension bridge of its time.
The Verrazzano-Narrows Bridge is currently the eleventh-longest span in the world and longest in the Western Hemisphere.
Ammann also assisted in the building of the Golden Gate Bridge in San Francisco, currently ranked twelfth.
Othmar Ammann was born near Schaffhausen, Switzerland, in 1879. His father was a manufacturer and his mother was a hat maker. He received his engineering education at the Polytechnikum in Zürich, Switzerland. He studied with Swiss engineer Wilhelm Ritter. In 1904, he emigrated to the United States, spending much of his career working in New York City. He became a naturalized citizen in 1924. 
In 1905 he briefly returned to Switzerland to marry Lilly Selma Wehrli. Together they had three children –  Werner, George, and Margot – before she died in 1933. He then married Klary Vogt Noetzli, herself recently widowed, in 1935 in California.
Ammann wrote two reports about bridge collapses, the collapse of the Quebec Bridge and the collapse of the original Tacoma Narrows Bridge (Galloping Gertie). It was the report that he wrote about the failure of the Quebec Bridge in 1907 that first earned him recognition in the field of bridge design engineering. Because of this report, he was able to obtain a position working for Gustav Lindenthal on the Hell Gate Bridge. By 1925, he had been appointed bridge engineer to the Port of New York Authority. His design for a bridge over the Hudson River was accepted over one developed by his mentor, Lindenthal. (Lindenthal's "North River Bridge" designs show an enormous, 16+ lane bridge that would have accommodated pedestrians, freight trains, rapid transit, and automobile traffic. The bridge, which would have entered Manhattan at 57th Street, was rejected in favor of Ammann's designs primarily due to cost reasons.)
Ultimately, this became the George Washington Bridge. Under Ammann's direction, it was completed six months ahead of schedule for less than the original $60 million budget. Ammann's designs for the George Washington Bridge, and, later, the Bayonne Bridge, caught the attention of master builder Robert Moses, who drafted Ammann into his service. The last four of Ammann's six New York City bridges — Triborough, Bronx-Whitestone, Throgs Neck, and Verrazzano-Narrows Bridge were all built for Moses' Triborough Bridge and Tunnel Authority. In 1946, Ammann and Charles Whitney founded the firm Ammann & Whitney. In 1964, Ammann opened the Verrazzano-Narrows Bridge in New York, that had the world's longest suspended span of 4,260 feet (1,300 m), and was the world's heaviest suspension bridge of its time. The Verrazzano-Narrows Bridge is currently the eleventh-longest span in the world and longest in the Western Hemisphere. Ammann also assisted in the building of the Golden Gate Bridge in San Francisco, currently ranked twelfth.
Othmar Ammann