A thoroughly refurbished schooner Shenandoah was relaunched Saturday morning at Boothbay Harbor in Maine.

The Shenandoah, one of the Black Dog tall ships that sail from Vineyard Haven harbor, had undergone about six months of extensive rebuilding at the Boothbay Harbor Shipyard.

“We essentially did what is referred to as retopping — a rebuilding of the vessel from the waterline up,” said Bob Foster, a spokesman for the shipyard.

The work was the Shenandoah’s first major renovation since the vessel was built at the nearby Harvey Gamage Shipyard in 1964.

Mr. Foster said the work included placing 3,000 lineal feet of oak planks on the sailing ship’s hull, refastening 3,000 galvanized nails on the ship’s bottom, and constructing a new afterdeck. The shipyard spent about 10,000 man-hours on the renovation. The Shenandoah has been at the shipyard since last November.

A 700-ton marine railway at the shipyard carried the Shenandoah out of the water for the rebuilding project and back into the water last Saturday.

Capt. Bob Douglas, who designed the Shenandoah and continues to skipper the vessel, said the schooner boasts a better finish job than when first built. Captain Douglas has spent about a day every week at the shipyard during the renovation project.

The Shenandoah, which by design does not have an engine, is slated to spend the next couple of weeks at Boothbay Harbor, where she is being fitted with new sails. Captain Douglas said the vessel is slated to resume operating from the Vineyard in mid-June.

“The bottom line is that this turned the boat around,” helping ensure its continuing existence and operation, Captain Douglas said. “Most boats only go one way.”