"Hikers will love this demanding 22 km loop, an additional part of the GR 412 route called ‘Sentier des Terrils’ (slag heaps). (GR 412 Route: Borinage - Charleroi - Basse Sambre - Hesbaye - Bassin Liégeois).
It carries on to Charleroi rail station, passing through interesting tourist spots such as ‘Marchienne’ and ‘Monceau’ castles, ‘Martinet Mining site’ and its slag heaps and the chain of slag heaps at ‘Dampremy’ and 'La Docherie’.
The route includes the ascent of four slag heaps linked together by passages, paths and short crossings of secondary roads. Look out for the Boucle Noir (Black Loop logo).
Its not a typical trail but its sporty, unusual and challenging.
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