Bethlehem is a town in Litchfield County, Connecticut, United States. The population was 3,422 at the 2000 census. The town center was designated in the 2000 census as a census-designated place.The town's name has prompted thousands of visitors each December to mail their Christmas cards at the local post office in order to get a "Bethlehem" postmark. The post office also has nearly 100 Christmas-related stamps for customers to decorate their envelopes during the holiday season.Bethlehem is one of the two towns in Litchfield County served by the area code 203/area code 475 overlay. The other is the Town of Woodbury.