| Tärnsjö | |
|---|---|
| Coordinates: 60°09′N 16°56′E / 60.150°N 16.933°ECoordinates: 60°09′N 16°56′E / 60.150°N 16.933°E | |
| Country | Sweden |
| Province | Uppland |
| County | Uppsala County |
| Municipality | Heby Municipality |
| Area | |
| • Total | 1.89 km2 (0.73 sq mi) |
| Population (31 December 2010) | |
| • Total | 1,221 |
| • Density | 645/km2 (1,670/sq mi) |
| Time zone | CET (UTC+1) |
| • Summer (DST) | CEST (UTC+2) |
Tärnsjö is a locality situated in Heby Municipality, Uppsala County, Sweden, with 1,221 inhabitants in 2010.