Streams and basins (Derived from 1km DEM; Pb. 2007)

- Global Drainage Basin Database (GDBD): Center for Global Environmental Research at the National Institute for Environmental Studies;.
- Free, downloadable; Publish: 2007.
- Derived from DEM: H1k-DEM (HYDRO1k), 1 km resolution by USGS 2000
(250m resolution in Japan; 3 seconds resolution in Korean Peninsula)
- ArcGIS Geodatabase format
<http://www-cger.nies.go.jp/cger-e/db/enterprise/gdbd/gdbd_index_e.html>

Layers
- Drainage basin boundary (polygon)
- River network (polygon)
- Discharge gauging station (point)
- Natural lake (point)
- Dam lake (point)
- Flow direction (raster)