The lighthouse on Amelia Island marking the entrance into the St. Mary’s River and the border between Florida and Georgia has been in use since 1820, but has been located in 2 different states. Originally built on Little Cumberland Island in Georgia it marked the southernmost point of the U.S. Atlantic coast. Florida remained under Spanish control until 1821. After the navigational channel into the mouth of the river shifted to the south in the 1830’s the decision was made to dismantle the lighthouse and rebuild it on the northern end of Amelia Island on the Florida side of the St. Mary’s River.