Museum representatives presented their plans for the site at a Washington County Commissioners meeting in Boonsboro Tuesday night.
"We want to get CSX to the bargaining table," Knode said.
The property hasn't been used since 1989, Knode said. The roundhouse, with 25 stalls and a 115-foot turntable, is the second largest east of the Mississippi, according to the museum.
"We think the time is right for development," Knode said. The property could generate jobs, including railroad maintenance work, he said.
Knode said CSX has donated properties in the past, and hoped that they would do so in this case.
The spot would be a natural location for a MARC station should the service expand to Hagerstown, Knode said.
Funding for the project could come from donations, government grants and operating income, officials said. But the museum won't be able to raise the needed money without the property, Knode said.
The County Commissioners agreed to write a letter in support of the museum to CSX. Hagerstown Mayor Steven T. Sager wrote a similar letter in November.