NY 100A is a loop off of NY 100 that bypasses the section in the downtown area of White Plains. It begins at Central Park Avenue (NY 100) in Hartsdale and runs to Elmsford, where there are grade-separated interchanges with Tarrytown Road (NY 119) and the Cross Westchester Expressway (I-287). Just north of the expressway, it changes names from West Hartsdale Avenue to Knollwood Road. It continues north to Valhalla, where it ends at NY 100 and NY 100C. The entire length is a two-lane undivided road.
Copyright © 2003-2019 by David Golub. All rights reserved. The author would like to thank William Roll for contributing photographs and LC for contributing documents to this web site. You may not reproduce any text or photographs on this web site without express permission from the author. Hotlinking of images from this site is strictly prohibited. Route symbols based on graphics from Central PA/MD Roads and Wikipedia.