PORTLAND, Maine — A Civil War-era fort at the entrance to Portland Harbor is closing for improvements.

Officials say Fort Gorges is closing from Monday through early October for safety improvements such as the installation of railings and gates.

Friends of Fort Gorges hope to one day host public events at the site including musical and theater performances.

The fortress is open to the public but can be accessed only by private boats.

The fort is named after Sir Ferdinando Gorges, who in the early 1600s was credited with discovering the land that is now Maine.