Downtown Plainfield serves as the community’s historic commercial and civic hub, featuring 50 properties along Lockport Street that showcase its evolution from 1848 to 1963. The district’s architecture spans Greek Revival, Italianate, and Queen Anne styles, with Greek Revival so prominent that early Lincoln Highway guides urged travelers to stop and admire it. A standout is the Queen Anne–style Masonic Block, designed by J.E. Minott and built in 1892 after a fire devastated much of the area; its distinctive onion dome remains an iconic landmark. Recognized for its rich history, Downtown Plainfield was listed on the National Register of Historic Places in 2013.