Located in theparc naturel régional des Ballons des Vosges, the village of Sondernach shares withMittlach the benefit of being situated on the slopes of a large valley watered by one of the streams forming the riverFecht. The altitude of the centre is between 500 and 600 metres.
Its only immediate neighbour is the commune ofMetzeral to the north.
The origin of the village's name is unclear. It could be fromder Sonne nahe meaning "near the Sun", orzum sundern Ach meaning "near the south stream", Sondernach being the furthest south village in the valley.
Sondernach first appears in archives in the 12th century. Around 1240, the BenedictineAbbey of Munster owned lands in the village. From 1287, the village was made part of the valley community groupingMunster and the ten communes of the Fecht. It was destroyed during theFirst World War, during the battle ofMetzeral, in June 1915.