The cemetery officially opened on October 26, 1869, after being converted from a farm. It covers. The cemetery was established by the benevolent order of the Knights of Pythias, for the interment of their members and others. The company was chartered on December 9, 1869 and bought the property, which had been "Mount Airy", the residence of Commodore Stephen Decatur, Sr. Originally chartered as "The Greenwood Cemetery Company of Philadelphia", the charter was changed to the "Knights of Pythias Greenwood Cemetery Company of Philadelphia" on March 18, 1870. Greenwood Cemetery was modeled after the rural cemetery movement of the mid 19th century. Designed by architect Thomas S. Levy, the plans for the cemetery were very grand with rolling hills, naturalistic plantings, pathways arranged in a spoke-and-circle pattern, an artificial lake and a large gatehouse. The gatehouse and lake were never realized. Portions of the historic house at the entrance date back to 1750-1775. Dr. Benjamin Rush, a signer of the Declaration of Independence, lived on the farm in the late 18th century. In the early 19th century, a major addition to the house gave it the appearance of a vernacular federal structure. Recent evidence, however, dates the construction of the house to the 1830s or later. Behind the house is a receiving vault emblazoned with Knights of Pythias insignia and inscribed with a date of 1870. On August 9, 2000, Greenwood was listed by the Philadelphia Historical Commission on the Philadelphia Register of Historic Places. The cemetery contains about 40,000 graves. The oldest grave is unknown, as there were many burials before the cemetery was chartered in 1869, and early records have been lost, but it is believed that it holds the remains of veterans of the Revolutionary War. Over the years, maintenance was neglected. While remnants of the landscaping and plantings typical of a rural cemetery are evident, the cemetery has been the victim of vandalism, with numerous overturned, fallen, and broken tombstones, and the rear of the cemetery reverted to woods. In 2000, the cemetery came under the management of Willow Ridge Ltd., a private company. There was considerable local controversy over the company's plan to raze the historic home and build new structures, including a funeral parlor and crematorium. In 2000, Philadelphia's Zoning Board of Adjustment granted permission for the funeral parlor and crematorium. Several local residents sued in Philadelphia Common Pleas Court to overturn the Board's decision. The court upheld the decision of the Board, and the residents appealed to Pennsylvania Commonwealth Court. On February 8, 2007, Commonwealth Court overturned the decision of the trial court. The cemetery owners then appealed to the Pennsylvania Supreme Court, but their appeal was denied on October 18, 2007. The Friends of Greenwood Cemetery, a nonprofit organization established in 2003, dedicated to preserving the records, tombstones, and grounds of the cemetery, made some progress in cleaning it up, mowing the lawns and clearing some of the woods. In 2008, an adjacent hospital, Cancer Treatment Centers of America at Eastern Regional Medical Center, through their sister company Greenwood Holdings, acquired a majority share of the cemetery. Greenwood Holdings has begun revitalizing the cemetery. Headstones have been righted; abandoned cars and appliances have been removed. In addition, more than 2,400 graves were moved from a wooded section in order to allow CTCA's expansion. More than $1 million has been spent on renovations of the historic house. Windows, floors, fireplaces, roofs, ceilings and walls were restored.
