What was France's famous defense line in World War II?

During World War II, there was a famous defense line on the German-French border called maginot line.

Shortly before World War II, France was forced to build the maginot line on the German-French border, which amazed future generations. 1929 started construction and 1940 was completed. The main body of the defense line is 700 kilometers long, all made of reinforced concrete.

At that time, * * * cost 5 billion francs, equivalent to the budget of France for several years at that time. All kinds of machine guns and cannons, trenches, kitchens, power stations, hospitals, factories and so on. In the defense line, the passages extend in all directions, and there are tram passages in the larger fortifications.

But the Germans once attacked from the Ardennes on the French-Belgian border, making maginot line the laughing stock of the world.

Extended data:

1940, the tank of General heinz guderian, the father of Blitzkrieg, opened a big hole on the Belgian-French border. German troops poured into the Ardennes forest, outflanked the French army and isolated maginot line.

Forty-four German divisions following guderian tanks directly plunged into the forest by means of civilian roads. The Belgians didn't implement the resistance plan at all, such as setting up roadblocks, digging traps and destroying roads as predicted by Petain.

Faced with the rapidly advancing invaders, about 40 French divisions were imprisoned in maginot line. They "defend but not defend", just as they exist to defend the defense line itself. About 30 other divisions are scattered on the line from Montmedi, the end of the Maginot line, to the English Channel.

References:

Baidu Encyclopedia-maginot line