| Official Name: | Castine, Maine |
| Settlement Type: | Census-designated place |
| Pushpin Map: | Maine#USA |
| Pushpin Label: | Castine |
| Pushpin Label Position: | left |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Maine |
| Subdivision Type2: | County |
| Subdivision Name2: | Hancock |
| Subdivision Type3: | Town |
| Subdivision Name3: | Castine |
| Unit Pref: | Imperial |
| Area Footnotes: | [1] |
| Area Total Km2: | 4.01 |
| Area Land Km2: | 3.99 |
| Area Water Km2: | 0.02 |
| Area Total Sq Mi: | 1.55 |
| Area Land Sq Mi: | 1.54 |
| Area Water Sq Mi: | 0.01 |
| Population As Of: | 2020 |
| Population Total: | 1014 |
| Population Density Km2: | 253.93 |
| Population Density Sq Mi: | 657.59 |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation Ft: | 85 |
| Coordinates: | 44.3886°N -68.7989°W |
| Postal Code Type: | ZIP code |
| Postal Code: | 04420, 04421 |
| Area Code: | 207 |
| Blank Name: | FIPS code |
| Blank Info: | 23-11230 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 2630699 |
Castine is a census-designated place (CDP) in the town of Castine in Hancock County, Maine, United States. The CDP population was 1,029 at the 2010 census,[2] out of 1,366 people in the town as a whole.
The Castine CDP occupies the southern end of the town of Castine, occupying the entire peninsula on which the town's main village of Castine is located. It is bordered to the west by Penobscot Bay, to the south by Castine Harbor and the tidal Bagaduce River, to the northeast by Hatch Cove, and to the northwest by Wadsworth Cove, an arm of Penobscot Bay. The CDP crosses the "British Canal", a small waterway cutting the isthmus and connecting the two coves, and extends north as far as Shore Road.[3]
Maine State Route 166 has its southern terminus in Castine, and leads north 7miles to West Penobscot. Bucksport is north of Castine via Routes 166, 175, and 1.
According to the United States Census Bureau, the Castine CDP has a total area of 4sqkm, of which 0.02sqkm, or 0.40%, are water.[2]
The Maine Maritime Academy is located in the Castine CDP.