New Windsor is a town in Carroll County, Maryland, United States. The population was 1,396 at the 2010 census. It is located 6 miles (10 km) west of Westminster on Maryland Route 31.
New Windsor was laid out in 1797 and originally named Sulphur Springs. It was renamed in the early 19th century, possibly after its English namesake. Since 1942, it has been headquarters for the international missionary efforts of the Church of the Brethren. These efforts inspired the international focus of the Peace Corps, whose first director, Sargent Shriver, had roots in the area. The town was considered an escape for the rich, and because of the Sulphur Springs, had a renowned spa by the water. New Windsor was home to Calvert College from 1852-1873 and later to New Windsor College. Much of the town was added to the National Register of Historic Places as the New Windsor Historic District in 1997. Avalon, a historic home, was listed in 1987 and the Appler-Englar House in 2001.