For more than a century, the brick Hoosac Warehouse has stood in the shadow of the USS Constitution, the historic warship that draws about 500,000 tourists to Charlestown every year.
The six-story building has served as a storage facility, and later a chocolate factory, but now sits vacant on the edge of the Charlestown Navy Yard.
On Friday, the leaders of the US Navy and US Department of the Interior announced the nondescript structure will play a key role in the future of the historic site during a ceremony near “Old Ironsides.”
Interior Secretary Ryan Zinke said the federal park system in Boston will get $3 million to draw up plans to transform the warehouse into the new home of the USS Constitution Museum and a visitor center run by the National Park Service.
“This is a transformational moment in Charlestown. It’s working with our partners to build something greater for the future,” said Zinke.
Officials from the museum, which is operated by a private nonprofit, and the park service, said the combined facility will make it easier for tourists to visit the USS Constitution and enhance their understanding of the Navy Yard and its history.
Many visitors come to the site from the Freedom Trail and find navigating the property difficult because of its confusing layout, according to a report commissioned by the museum, Navy, and National Park Service.
The museum and visitor center are housed in separate buildings on different sides of the property. Tourists who want to board the ship must pass through a security checkpoint located next to the visitor center.
“It’s a maze when you come in now,” said Anne Grimes Rand, president of the USS Constitution Museum. “It’s tough on visitors.”
The plan for Hoosac Warehouse would bring the security checkpoint, visitor center, and museum under one roof.
“It will give visitors to Boston a much better sense of why they’re here and what this is all about,” Rand said.
Michael Creasey, general superintendent of the National Parks of Boston, said the design process should take about 18 months.
“This really puts the focus on what’s important,” Creasey said. “National parks are created to tell stories. They’re created to preserve our heritage. That’s what this project is about.”
The Hoosac Warehouse has about 60,000 square feet, half of which would be used for the museum, Rand said. The museum’s current home would host educational programming for large groups, she said.
Suzanne Gall Marsh attended the ceremony with students at the Osher Lifelong Learning Institute at the University of Massachusetts Boston. Marsh, who teaches a class about maritime sites in the region, said the Hoosac Warehouse, in its current state, looks like a wall.
“This plan makes it much more welcoming and open,” she said.
The visit from Zinke, who was joined by Navy Secretary Richard V. Spencer, drew some protesters, who displayed signs and waved small American flags.
A group of veterans and Sierra Club representatives said they oppose a proposal from Zinke and a bipartisan group in Congress that would use revenues from energy leases on public lands to pay for upgrades at national parks.
Matt McLaughlin, a Somerville alderman and veteran, shared video with the Globe of him confronting Zinke. The men shook hands and spoke briefly, but Zinke declined to discuss the issue with him, according to the video.
“He’s bragging about serving the parks but he’s only serving the parks through exploiting them,” McLaughlin said in an interview. “He’s weakening the park system.”
Laura Crimaldi can be reached at firstname.lastname@example.org. Follow her on Twitter @lauracrimaldi.