This is not the Maginot Line.
This picture is showing turrets from the Metz fortress, built by the Germans in the occupied Lorraine between 1871 and 1918. These are 105 mm guns, that were not in use in THE Maginot Line.
The fortress was modernized and refitted to the french standards between the wars.
The french propaganda used a lot the Metz fortress with displays for the international press. The Maginot Line was top secret during the Phoney War, and it was forbidden to publish pics of it. That's why they just allowed the journalists to take pics of the less well designed Metz fortress.
In the Maginot Line, such a concentration of turrets on a so tiny area, these external barrels easily taken out and non-retractable turrets would be an heresy.
ALL the turrets in the Maginot Line were looking like this:
