Oostkust Sumatra. Schetskaart der Siak Rivier van het Eiland Tengah tot Siak
1894
Indonesia
This late 19th century large-scale (1:30,000) map show just a section of the Siak River, in the Riau province of Sumatra. Bathymetry (water depth) is shown in figures to aid navigation, with various landmarks noted along the river’s banks.