St. Johns River Light in Jacksonville, Florida, built in 1858 near the mouth of the St. Johns River, is the third lighthouse at the river entrance, the oldest one still standing there, and Mayport’s oldest surviving building. It was erected taller and farther from shore after two earlier lighthouses failed because of water exposure, shifting sand, and erosion. During the Civil War, Confederate authorities extinguished the light, and keeper John Daniels was later arrested by Federal forces on suspicion of signaling from the tower. The light was relit in 1867, remained in service until 1929, and was later restored after Navy alterations to the site.