| Official Name: | Östergarn |
| Native Name: | Austagan |
| Pushpin Map: | Sweden Gotland |
| Subdivision Type: | Country |
| Subdivision Name: | Sweden |
| Subdivision Type3: | Municipality |
| Subdivision Name3: | Gotland Municipality |
| Subdivision Type2: | County |
| Subdivision Name2: | Gotland County |
| Subdivision Type1: | Province |
| Subdivision Name1: | Gotland |
| Area Footnotes: | [1] |
| Area Total Km2: | 28.29 |
| Population As Of: | 2014 |
| Population Footnotes: | [2] |
| Population Total: | 347 |
| Timezone: | CET |
| Utc Offset: | +1 |
| Timezone Dst: | CEST |
| Utc Offset Dst: | +2 |
| Coordinates: | 57.4217°N 18.8586°W |
Östergarn (in Swedish pronounced as /ˈœ̂sːtɛrˌɡɑːɳ/)[3] is a populated area, a socken (not to be confused with parish), on the Swedish island of Gotland.[4] It comprises the same area as the administrative Östergarn District, established on 1January 2016.[5]
Östergarn is situated on a peninsula on the central part of eastern Gotland. The area has several low plateaus, the two major ones are Grogarnsberget and Östergarnsberget.[6] [7] The medieval Östergarn Church is located in the socken.[8], Östergarn Church belongs to Östergarn parish in Romaklosters pastorat, along with the churches in Gammelgarn,Kräklingbo, Anga and Ala.[9] [10]
The harbor village Katthammarsvik is on the north coast of Östergarn and the Herrvik fishing village is on the eastern tip of the peninsula. About 4km (02miles) northeast of Herrvik is the Östergarnsholm island with its two lighthouses.[11] The island is about 200ha. Along the southern coast is the Sandviken Natura 2000 nature reserve with its long, sandy beach.[12] [13]
One of the asteroids in the asteroid belt, 10815 Östergarn, is named after this place.[14]