Manhasset Viaduct
The Manhasset Viaduct is a railroad viaduct located between Manhasset and the Village of Thomaston within the Town of North Hempstead, on Long Island, New York. It carries the Port Washington Branch of the Long Island Rail Road over Manhasset Bay, between the Cow [Neck Peninsula|Cow Neck] and Great Neck Peninsulas.
Overview
Standing at a height of above Manhasset Bay and measuring in length, the Manhasset Viaduct is the highest bridge on the entire LIRR network. The viaduct uses a steel stringer bridge design and is one of two King Bridge Company-built railway viaducts still in operation as of 2025 – the other being the Short Line Viaduct near Cleveland, Ohio.The Manhasset Viaduct is a critical component of the infrastructure on the LIRR's Port Washington Branch. Its construction enabled the railroad line to traverse the Manhasset Valley and Manhasset Bay: due to the surrounding area's geographical and topographical characteristics, the LIRR could not extend the line into Manhasset and Port Washington – both communities being located across the valley, on the Cow Neck Peninsula – without it building a viaduct over it and the bay.
The viaduct also passes over two major roads – one on each end: East Shore Road and Bayview Avenue.
History
The Manhasset Viaduct was completed in 1898, and opened on June 23 of that year, as part of the Port Washington Branch's extension from Great Neck to Port Washington. It was erected by the Cincinnati, Ohio-based King Bridge Company, as well as the Carnegie Steel Company, and was constructed using Carnegie Steel.In 1913, the remainder of the Port Washington Branch between the line's split with the former Whitestone Branch east to Port Washington – including the portion of the line over this bridge – was electrified with a third rail, thus enabling electric trains to operate along the entire line; the electrification officially took place on October 21 of that year.