They were also the first to apply the concept of "defence in depth", where the front-line zone was hundreds of metres deep and contained a series of redoubts rather than a continuous trench.
Tamén foron os primeiros en aplicar o concepto de "defensa en profundidade", onde as liñas frontais tiñan centos de metros de profundidade e contiñan unha serie de postos de avanzada en lugar dunha trincheira continua.