St. Johns River Light, Maritime beacon at Naval Station Mayport, Florida, United States.

The St. Johns River Light is a lighthouse in Mayport, Florida, built with red brick and topped with a copper cupola. A white watch room sits beneath the cupola, and slate stairs run through the interior of the structure.

This structure was built in 1858 to guide ships entering the St. Johns River. It operated for more than 70 years before being decommissioned in 1929, when an offshore lightship took over its duties.

The tower's name comes from the river it marked, and locals call it the "Old St. Johns River Light" to tell it apart from the 1954 St. Johns Light two miles southeast. The keeper John Daniels stayed on after Confederate authorities put the light out in 1861; Federal troops arrested him over a night signal that turned out to be moonlight. The Mayport Lighthouse Association now works toward a full restoration and public opening.

The tower stands inside Naval Station Mayport, so access is restricted; the original door is buried and entry would be through a window eight feet up. Views of the exterior are possible from public areas of the Mayport village outside the base perimeter. The Mayport Lighthouse Association hopes to fully restore it and open it to the public.

This is the oldest surviving building in Mayport, with roots reaching back to the mid-1800s. Its age makes it a rare example of early American lighthouse construction in the region.