The Greensburg Downtown Historic District of Greensburg, Pennsylvania, is bounded approximately by Tunnel Street, Main Street, Third Street, and Harrison Avenue. It consists of 62 buildings on 21.8 acres (8.8 ha), with the most notable buildings from the years 1872-1930. The district's oldest structure (1872) is the former Masonic Temple at 132 South Main Street. The Academy Hill Historic District is directly to the north of downtown Greensburg.
Two places that are separately listed on the National Register, the Westmoreland County Courthouse and the Greensburg Railroad Station, are included in the district. The "dominant building" in the district is the courthouse.Downtown Greensburg was once a significant retailing center, serving numerous small communities in central Westmoreland County. Not only was it an important station on the Pennsylvania Railroad, but it was also the headquarters of West Penn Railways, an interurban (long-distance trolley) company serving many small communities to the east and south of Greensburg. The headquarters building of West Penn Railways is still extant at 416 South Main Street, serving as City Hall, although it is outside the boundaries of the historic district. These forms of rail transportation contributed to Greensburg's growth in the pre-automobile era.
Greensburg's largest department store was Troutman's (202-226 South Main Street), the only downtown building with escalators. Other department stores included Royer's (114 South Main Street), Sears (101 North Main Street), and J. C. Penney (221 South Main Street, in a building previously used by Pollins' Grand Depot department store). The first three department stories remain standing, converted to other uses; however, the J. C. Penney building was demolished in 2022. The opening of Greengate Mall in 1965 (now demolished) had a devastating impact on downtown retailing, following the pattern that occurred in numerous communities. However, the presence of the courthouse continues to give purpose to downtown, and a significant number of historic properties remain.