NEW CASTLE — The Delaware Division of Historical and Cultural Affairs has temporarily closed the New Castle Court House Museum in order to install a fire sprinkler system.

While the project is underway, the contents of the historic museum are being preserved from any potential damage in the installation process. Museum employees are also be able to work from alternate locations in the building while the installation takes place.

The New Castle Court House was built in 1732. The building was once the original Delaware state capitol and the state’s first court. For over 200 years, it has been an important political and social site for the local community.

The location was registered as a National Historic Underground Railroad Site in 2003, and in 2013, the New Castle Court House Museum joined Delaware’s First State National Historical Park as a partner site.

The building is one of the oldest standing courthouses in the United States, and its unique history makes it one of the busiest historical sites in the state.

The contractors for the project, as well as the design plans, were approved by the Division of Historical and Cultural Affairs, the State Preservation Office and the National Park Service before installation began.

The contractors were required to have previous experience working on historical buildings, as the initiative is to make the courthouse a safer place for visitors and its employees.

The project, which is being contracted by Bathon Builders, is expected to cost approximately $429,700.

The museum closed on Dec. 31 to begin the installation process, and the Division of Historical and Cultural Affairs anticipates the reopening of the museum in the spring.