It was once much longer, as it originally extended east along NY 17A and CR 106 in Orange and Rockland counties to Stony Point when it was assigned as part of the 1930 renumbering of state highways in New York.

[4][5] This 20-mile (32 km) extension was primarily made up of several highways that were previously part of a privately maintained road.

On March 10, 1824, the New York State Legislature passed a law incorporating the Monroe and Haverstraw Road Company.

The highway was subsequently sold off in order to pay off the debts of the company and to finance repairs to bridges along the road.

Three years later, a portion of the route became part of Seven Lakes Drive, a major highway built to traverse the park.

The route continued east from there along Southfields Road to the eastern fringe of Harriman State Park, at which point it headed to West Haverstraw via Willow Grove and Letchworth Village roads, Suffern Lane, and Railroad Avenue.

[17][18] Over the years, at least two fatal accidents have occurred on the portion of NY 210 that runs alongside Greenwood Lake.

[19] On December 1, 1968, three were killed and one person was injured when two cars had a head-on collision just north of the New Jersey state line.