| Ätran | |
| Map: | Karta Aetran position.gif |
| Subdivision Type1: | Country |
| Subdivision Name1: | Sweden |
| Subdivision Type3: | County |
| Length: | 240km (150miles)[1] |
| Discharge1 Avg: | 47m3/s |
| Source1 Location: | Gullered, Västergötland |
| Source1 Coordinates: | 57.7725°N 13.5578°W |
| Source1 Elevation: | 332m (1,089feet) |
| Mouth: | Kattegat |
| Mouth Location: | Falkenberg |
| Mouth Coordinates: | 56.8883°N 12.4775°W |
| Mouth Elevation: | 0m (00feet) |
| Basin Size: | 3342.2km2[2] |
Ätran is a Swedish river. The river is about 240km (150miles) long, and has its source in Gullered, Västergötland, at a height of 332m (1,089feet) above sea level. The river has its mouth in Falkenberg, Halland, where the river enters Kattegat.
The drainage basin covers an area of 3343km2, mostly consisting of forest. The river is well known as a good place for fishing. It is comparatively unpolluted.
A historic road, Redvägen, followed the river, along which several medieval battles took place.
| Area/tributary | Drainage basin (km2) | Average water flow (m3/s) | |
|---|---|---|---|
| Ätran, upstream Åsunden | 650 | ||
| Ätran, between Åsunden and Assman | 379 | 8 | |
| Assman (Lillån) | 652 | 9.5 | |
| Ätran, between Assman and Kalvån | 45 | 24.5 | |
| Kalvån (Lillån) | 514 | 8.2 | |
| Ätran, between Kalvån and Högvadsån | 370 | 33.5 | |
| Högvadsån | 476 | 8.5 | |
| Ätran between Högvadsån and the Sea | 257 | 49 | |
| Total/Final | 3,343 | 52.5 |
The largest tributary is Högvadsån. Other main tributaries are Assman (Lillån), which join the river close to Örsås church, and Kalvån (Lillån), which join the river close to Östra Frölunda church.
The drainage basin include the major parts of Falkenberg, Svenljunga, Tranemo and Ulricehamn Municipalities. Smaller parts of Falköping, Borås, Gislaved, Mark, Hylte, and Varberg Municipalities are also part of the drainage basin. Within the basin, 64 percent of the area is forest, 6 percent is lakes, 7 percent is bogs, 11 percent is fields, and 12 percent is other.
The largest lakes within the basin are Åsunden (33.9 km2), Fegen (24.2), Sämsjön (9.2), Lönern (7.7) and Kalven (6.6). In total, there are about 200 km2 of lakes within the basin. A record of the water flow at Yngeredsfors Power Station has been kept; it was on average 37.2 m3/s from 1909 to 1967. The maximum flow was 275 m3/s, while the minimum flow was between 5 and 7 m3/s.