| Avenel-Hillandale | |
| Settlement Type: | Former CDP |
| Pushpin Map: | USA Maryland#USA |
| Pushpin Map Caption: | Location within the state of Maryland |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Maryland |
| Subdivision Type2: | Counties |
| Subdivision Name2: | Montgomery & Prince George's |
| Unit Pref: | Imperial |
| Area Land Km2: | 9.1 |
| Population As Of: | 1970 |
| Population Total: | 19520 |
| Population Density Km2: | auto |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Coordinates: | 39.0128°N -76.9781°W |
| Postal Code Type: | ZIP codes |
| Postal Code: | 20783 & 20903 |
| Area Code: | 301 & 240[1] |
| Blank Name: | FIPS code |
| Blank Info: | 24-03225[2] |
| Blank1 Name: | GNIS feature ID |
Avenel-Hillandale was a Census-designated place in Montgomery and Prince George's Counties in Maryland during the 1970 United States Census.[3] which consists of the communities of Avenel,[4] Hillandale and Adelphi. The population in 1970 was 19,520.[5] The census area reorganized to the present day CDPs of Hillandale and Adelphi in 1980.[6] The ZIP codes serving the area are 20783 and 20903.
Located at 39.0130 north and 76.9783 west, the census area of Avenel-Hillandale was bordered by the census areas of Silver Spring to the west, White Oak to the north, Beltsville to the northeast, Langley Park to the southwest and the city of College Park to the southeast.[7] The land area of the CDP was 3.5 square miles and a population density of 5,577 persons per sq. mi.[8]