PORTLAND — Friends of Fort Gorges has launched a $500,000 “Your Fort” fundraising campaign to help preserve the more than 150-year-old former military fort in Casco Bay.

If the group can raise $250,000, the city is offering a $250,000 match grant.

The fundraising campaign is the first for the organization, which is “committed to the restoration and preservation of Fort Gorges and ensuring access to facilitate its educational and cultural potential.”

The fort, which is owned by the city, was built between 1858 and 1864 and was used for storage during WWII. The federal government conveyed Fort Gorges to the city in 1960.

Paul Drinan, executive director of Friends of Fort Gorges, said the money would be used for masonry work and cribbing in the casements that used to house cannons and for improving access to the southwest parapet of the fort overlooking mainland Portland. The fort is less than a mile from Fort Allen Park on the East End.

While most of the 8,000 annual visitors to the site access it on their own through private watercraft, Friends of Fort Gorges is offering socially distant boat rides and tours of Fort Gorges.

For information about Friends of Fort Gorges or to donate visit friendsoffortgorges.org.