Seems to me that in order for a town to be considered a Rivertown they must have frontage on the Hudson River. Ardsley doesn't have any Hudson River waterfront yet a lot of people consider it a Rivertown. I don't. Ardsley, New York is a 1.3 mile Village. Ardsley has Route 9A running through the center. Proximity to the city, centrally located and close to all highways and great schools make Ardsley a popular place to settle. However it is not a Rivertown. In Westchester County the following communities have Hudson River frontage and would be considered "Rivertowns":
Yonkers, Hastings-on-Hudson, Dobbs Ferry, Irvington, Tarrytown, Mt. Pleasant (Sleepy Hollow), Ossining, Briarcliff Manor, Croton-on-Hudson, Cortlandt Manor and Peekskill.
"Historic Hudson River Towns is a consortium of communities located on the East and West banks of New York’s majestic Hudson River, from Yonkers to Albany."
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