A historic Coast Guard cutter that performed search-and-rescue missions between the Florida Keys and Cuba during the 1980 Mariel Boatlift arrived Tuesday in Key West to serve as a floating museum.

The 327-foot Ingham, launched at Philadelphia in 1936, is believed to be the most decorated vessel in the Coast Guard fleet. According to Coast Guard historical records, it is the only cutter ever awarded two Presidential Unit Citations.

Named for Samuel Ingham, who was Secretary of the Treasury in the 1800s, it is one of only two preserved Secretary class cutters.

In 1980, when more than 100,000 Cubans fled Mariel, Cuba, the Ingham was active in search-and-rescue missions in the waters off the Florida Keys and South Florida, rescuing refugees from swamped rafts and boats and escorting refugee vessels to safety in Key West.

The Ingham served during World War II, where it sank an enemy submarine while on convoy duty protecting ships that ferried supplies to Great Britain. It also served in the Korean War and earned Presidential Unit Citations for service during the Vietnam War.

Decommissioned in 1988, the preserved Ingham was a museum ship at the Patriots Point Naval Maritime Museum in Charleston, S.C., whose focus is on Navy ships. Facing financial burdens to repair other vessels in its fleet, the museum no longer could afford the $80,000 annual cost of maintaining the Ingham. A group of Key West residents decided to acquire the vessel that is now a registered National Historic Landmark, dedicated to Coast Guard personnel killed in action in World War II, Korea and Vietnam.

The Ingham is docked on Key West’s Truman Waterfront beside the USS Mohawk, another former Coast Guard cutter turned into a floating museum, and is scheduled to open to the public in December.