| Big Badja | |
| Name Other: | Badja |
| Map Size: | 250 |
| Pushpin Map: | Australia New South Wales |
| Pushpin Map Size: | 250 |
| Pushpin Map Caption: | Location of the mouth of the Big Badja River in New South Wales |
| Subdivision Type1: | Country |
| Subdivision Name1: | Australia |
| Subdivision Type2: | State |
| Subdivision Name2: | New South Wales |
| Subdivision Type3: | Region |
| Subdivision Name3: | South Eastern Highlands (IBRA), Monaro |
| Subdivision Type5: | Municipality |
| Subdivision Name5: | Cooma-Monaro |
| Length: | 32km (20miles) |
| Source1: | Big Badja Hill |
| Source1 Location: | north–east of Cooma |
| Source1 Coordinates: | -36.0528°N 149.55°W |
| Source1 Elevation: | 1030m (3,380feet) |
| Mouth: | Numeralla River |
| Mouth Location: | near Numeralla |
| Mouth Coordinates: | -36.1742°N 149.3478°W |
| Mouth Elevation: | 735m (2,411feet) |
| River System: | Murray–Darling basin |
| Tributaries Left: | Undoo Creek, Peppers Creek |
| Tributaries Right: | Boundary Creek (New South Wales) |
| Extra: | [1] |
The Big Badja River, a perennial river of the Murrumbidgee catchment within the Murray–Darling basin, is located in the Monaro region of New South Wales, Australia.
The river rises on the western slopes of the Great Dividing Range, north–east of Cooma at the junction of the Kybeyan and Gourock Ranges, and generally flows south and west, joined by three minor tributaries before reaching its confluence with the Numeralla River at the village of Numeralla; dropping over its course of .[1]
Alluvial gold was discovered in and along the river in 1858, with the Big Badja diggings worked between 1861 and 1868.[2]