A few kilometres of the upper reaches also flow through the German municipality Roetgen and form part of the Belgian–German border.

[2] The Vesdre's total length is approximately 64 kilometres (40 mi).

Its source lies in the High Fens (Hautes Fagnes, Hohes Venn, Hoge Venen), close to the border with Germany near Monschau.

The water of the Vesdre has a high acidity (due to the Hautes Fagnes bogs), which made it very suitable for the textiles industry around Verviers.

The Vesdre was the far eastern end of the sillon industriel, the backbone of Walloon industry.