Adelphi

History

The unincorporated Adelphi community takes its name from the historic Adelphi Mill, established in 1796 along the Northwest Branch of the Anacostia River. and continues to attract visitors and can be rented for special functions. During the 19th century, George Washington Riggs acquired much of the area northeast of Washington, D.C., as his Green Hill estate in the Chillum Manor district. That estate included present-day Adelphi. In the early 1920s, part of the area was acquired by Leander McCormick-Goodhart as part of his Langley Park estate. Labor organizer Mary Harris "Mother" Jones died in 1930, at the farm of Walter and Lillie May Burgess near Powder Mill and Riggs Roads in present-day Adelphi. A marker was erected by the Maryland State Highway Administration commemorating Mother Jones at her death site. Unlike its nearby neighbors Hyattsville and College Park, the area remained relatively undeveloped until immediately following World War II. At that time, subdivisions quickly developed. To distinguish it from the other neighboring unincorporated communities of Lewisdale and Langley Park, the growing subdivisions banded together in the mid-1950s and adopted the name "Adelphi" to reflect their commitment to the preservation of the historic mill of the same name. A community focal point that originally developed in the late 1950s is the Adelphi Pool, a private pool in the Adelphi neighborhood, located next to George Washington Cemetery on Riggs Road. Use of the Adelphi Pool requires paid membership or being accompanied by a member and paying a small fee. The Adelphi pool offers swimming lessons and also features swim teams which compete against each other. Two notable features of the Adelphi Pool are its long water slide and basketball hoop. In 1971, the Harry…

Geography

Adelphi is located at (38.996860, −76.966755). According to the United States Census Bureau, the Census Designated Place (CDP) has a total area of , all land. * Hillandale (northwest) * Beltsville (north) * Calverton (north) * College Park (southeast) * Hyattsville (south) * Lewisdale (southwest) * Langley Park (southwest) * Silver Spring (west)

Race & ethnicity

Most-observed species

• Northern Cardinal

  Cardinalis cardinalis (Linnaeus, 1758) · Aves
  164,198
• American Robin

  Turdus migratorius Linnaeus, 1766 · Aves
  147,445
• Carolina Wren

  Thryothorus ludovicianus (Latham, 1790) · Aves
  127,982
• Blue Jay

  Cyanocitta cristata (Linnaeus, 1758) · Aves
  126,382
• Mourning Dove

  Zenaida macroura (Linnaeus, 1758) · Aves
  119,386
• European Starling

  Sturnus vulgaris Linnaeus, 1758 · Aves
  110,928
• House Sparrow

  Passer domesticus (Linnaeus, 1758) · Aves
  107,430
• American Crow

  Corvus brachyrhynchos C.L.Brehm, 1822 · Aves
  106,319

Largest nearby schools

• High Point High
  High · Beltsville · 3,003 students · 18.4:1 ratio
• Charles Herbert Flowers High
  High · Springdale · 2,569 students · 21.1:1 ratio
• Parkdale High
  High · Riverdale · 2,561 students · 16.3:1 ratio
• Eleanor Roosevelt High
  High · Greenbelt · 2,526 students · 20.7:1 ratio
• Duval High
  High · Lanham · 2,503 students · 19.7:1 ratio
• Northwestern High
  High · Hyattsville · 2,346 students · 16.5:1 ratio
• Bladensburg High
  High · Bladensburg · 2,164 students · 16.5:1 ratio
• Laurel High
  High · Laurel · 2,134 students · 17.8:1 ratio

Most recent

• M 2.5 — 2025-10-27
  4 km E of Riverside, Maryland
• M 2.6 — 2021-06-25
  2 km SE of Woodlawn, Maryland
• M 3.03 — 2016-01-17
  3 km NE of Ranson, West Virginia
• M 3.6 — 2010-07-16
  5 km NNW of Barnesville, Maryland
• M 2.5 — 2001-06-25
  8 km S of Remington, Virginia