on Thomas Park and the monument, was listed as the Dorchester Heights Historic District on the National Register of Historic Places in 2001, encompassing the period of residential development of the area beginning in the later decades of the 19th century. The Dorchester Heights monument area was separately listed on the National Register in 1966. Monument An area near the top of Telegraph Hill was used as the site of a reservoir to provide water to South Boston in 1849, with water provided from Lake Cochituate in the western suburbs. This reservoir was later filled in and South Boston High School was built on the site in 1901. The rest of the summit of the hill was developed as Thomas Park in the 1850s, a roughly elliptical park with ornamental plantings and walkways. During restoration work in the 1990s, archaeologists uncovered evidence of the Revolutionary War fortifications, previously thought to have been destroyed by the park's construction. The Dorchester Heights Monument, located at the center of Thomas Park, was completed in 1902 to designs by Boston architects Peabody and Stearns. It is 115 feet (35m) tall, built of Georgia white marble capped with octagonal cupola and weather vane, and is generally reminiscent of a church steeple in the Federal style. The monument is now operated by the National Park Service as part of Boston National Historical Park. See also National Register of Historic Places listings in southern Boston, Massachusetts References Notes Sources National Park Service: Dorchester Heights National Register of Historic Places in Boston Landmarks in South Boston American Revolutionary War sites in Massachusetts Peabody and Stearns buildings Geography of Suffolk County, Massachusetts Boston National Historical Park Historic districts in Suffolk County, Massachusetts