Our Lady Star of the Sea Catholic Chapel is located at 106 E. Dillingham Street in St. Marys, Georgia. Originally a bank built in 1840, which failed after seven years, the building was purchased and the church established in 1847.

The First Presbyterian Church of St. Marys is located at 100 W. Conyers Street in St. Marys, Georgia. Built in 1808, it is the oldest building in Georgia in continuous use as a church. Originally non-denominational, it became a Presbyterian church in 1822 and is the oldest Presbyterian church in Georgia. It is also the second oldest church in Georgia.