length = corridors * 3
    width  = rows * 3

    -- main row

    -- this is the waypoint for the beginning of the mine
    Turtle.addWayPoint()

    Turtle.digCorridor2(length, 2)

    Turtle.goToLastWP({})


    -- make corridors
    for i = 1, corridors+1 do
        Turtle.turnLeft()
        Turtle.digCorridor1(width, 2)
        Turtle.back(width)
        Turtle.turnAround()
        Turtle.digCorridor1(width, 2)
        Turtle.back(width)
        Turtle.turnLeft()

        if i == corridors+1 then
            Turtle.forward(3)
        end
    end
    -- go back to first position
    Turtle.goToLastWP({})