Caln, PennsylvaniaCaln is a census-designated place in Caln Township, Chester County, Pennsylvania, United States. The population was 1,519 at the 2010 census. It is located east of the city of Coatesville and lies west of Philadelphia.GeographyCaln is located at. The Lincoln Highway, also known as U.S. Route 30 Business, forms the southern edge of the CDP. Caln CDP extends north as far as Pennsylvania Route 340. According to the U.S. Census Bureau, the CDP has a total area of, all land.EducationThe school district is Coatesville Area School District.