detail of St. Michael's Episcopal church and post office in Charleston, SC. St. Michael's Church is an historic church and the oldest surviving religious structure in Charleston, South Carolina. It is located at Broad and Meeting streets on one of the Four Corners of Law, and represents ecclesiastical law. It was built in the 1750s by order of the South Carolina Assembly. It is listed on the National Register of Historic Places and is a National Historic Landmark. he clock is the oldest tower clock in North America. The bells are one of four sets (Grace Episcopal, The Cathedral of Saint Luke and Saint Paul and Stella Maris Catholic church) in the Charleston area.