West Side Elevated Highway

The West Side Elevated Highway (West Side Highway or Miller Highway, named for Julius Miller, Manhattan Borough President, 1922–30) was an elevated section of Route NY-9A running along the Hudson River in the New York City borough of Manhattan to the tip of the island. It was an elevated highway, one of the first urban freeways in the world, and served as a prototype for urban freeways elsewhere, including Boston's Central Artery.

Built between 1929 and 1951, the highway's narrow confines – which could not accommodate trucks – and sharp S exit ramps made the highway obsolete almost immediately. Maintenance was minimal, and the use of corrosive salts to de-ice the highway in winter accelerated its decay. When chunks of the highway's facade began to fall off due to lack of maintenance, and a truck and car fell through it at 14th Street in 1973, the highway was shut down, and a debate began whether to renovate it or dismantle it. Attitudes about urban planning had changed in the intervening decades, and the decision was made not to repair the decaying structure.

The need to replace the deteriorating highway was recognized in the 1950s. Plans were drafted, but not executed. By 1971, a plan evolved for the elevated highway to be replaced by an underground interstate-quality highway, which came to be called Westway. It received approval from many levels of government, from the City to the Federal, but was scuttled in 1985 due to environmental issues. In the interim between the closure of the elevated highway and the completion of its dismantling, while debate about Westway was proceeding, remaining sections of the old highway structure began to be unofficially utilized as an elevated urban park, for jogging and bicycling.

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