| Glogn | |
| Name Other: | German: Glenner |
| Length: | 30.7km (19.1miles) |
| Source1 Coordinates: | 46.6019°N 9.0689°W |
| Source1 Elevation: | 2500m (8,200feet) |
| Mouth Coordinates: | 46.7767°N 9.2122°W |
| Mouth Elevation: | 688m (2,257feet) |
| Subdivision Type1: | Country |
| Subdivision Type2: | Canton |
| Subdivision Type3: | Cities |
| Subdivision Name3: | Ilanz |
| Custom Label: | Access |
| Custom Data: | Lower reaches navigable using a kayak--> |
The Glogn (Romansh, German: Glenner) is a whitewater river in Graubünden. Glenner was also the name of a district in this area, which was annexed by Surselva District in 2001.
The river rises near the border with Ticino and is surrounded by up to 3100m high mountains. The river flows through the Lumnezia. In Suraua, the Vals Rhine flows into the Glogn. After a few more kilometers, the Glogn flows into the Vorderrhein at Ilanz. In the upper reaches of the river has cut a deep gorge, which has uncovered black shale in a few places. During the snow melt and after rains the river water is usually dark gray.