Les étangs Gründel

The Gründel ponds, located at the center of a forest crossroads to the north of the Forêt d?Exception® de Haguenau, are known as "Grünes Wasser" (green ponds). These two shallow ponds were dug at the end of the 19th century to extract the gravel and sand needed to build the railroad line between Mertzwiller and Seltz, commissioned in 1893. This line then served the Maginot Line before being destroyed during the Second World War. Now cleared of trees and undergrowth, parts of the line are used as a hiking trail.
From March onwards, several species of frogs and newts lay their eggs in these ponds. Surrounding the ponds are oil wells, some of which are still visible, and were in operation until the 1970s.