It is an expansion of an earlier listing of the Essex County Court Buildings on the National Register of Historic Places in 1976.

In addition to the former county court buildings included in the earlier listing, the district expansion in 1983 encompasses the entire block of Federal Street between Washington and North Streets.

The Old Granite Courthouse, also known as the County Commissioner's Building, was built in 1841 in the Greek Revival architectural style.

Built in 1862, the Superior Court is an Italianate structure that was later remodeled into the Richardsonian Romanesque style of architecture.

The notable exception is #47, which is a Georgian gambrel-roofed house built in the second half of the 18th century.