- Western Terminus:
- NY 28 in Boiceville
- Eastern Terminus:
- Onteora Trail (NY 28) in Hurley
- 19.75 miles
NY 28A is a loop off of NY 28 running along the south side of the Ashokan Reservoir, while NY 28 runs along the north side. NY 28A is also known as New York City Road and BWS Road because it is under the jurisdiction of the Bureau of Water Supply, an agency within the New York City Department of Environmental Protection. It has special reference markers with "NYC" on the first line. New York City is involved here because the reservoir is part of the city's water supply, despite being almost 100 miles from the city.