Thiells, known as Thiell's Corner in the 1850s, is a hamlet and census-designated place (CDP) in the town of Haverstraw, Rockland County, New York, United States. It is located north of Mount Ivy, east of Pomona, south of Tomkins Cove, and west of Garnerville. The population was 5,240 as of the 2020 census.

Haverstraw is a town in Rockland County, New York, United States, located north of the Town of Clarkstown and the Town of Ramapo; east of Orange County; south of the Town of Stony Point; and west of the Hudson River. The town runs from the west to the east border of the county in its northern section. The population was 39,087 at the 2020 census.