A method for determining if a stretch of casting line includes the closing position of the liquid cone of a continuously cast metal product, wherein there is provided a casting line comprising - an ingot mold containing the liquid metal and in which a meniscus is defined, - one or more soft reduction devices with rolls, - actuating cylinders for actuating said one or more soft reduction devices, - at least two areas of application of a periodic oscillating impulse along the casting line, said at least two areas defining end areas of said stretch of casting line, the method comprising the following stages: a) sequentially applying a first periodic oscillating impulse to a first area of application represented by a first actuating cylinder, thus causing a first oscillation on the cast product, and then a second periodic oscillating impulse to a second area of application represented by a second actuating cylinder, thus causing a second oscillation on the cast product; b) detecting the oscillating frequency of the meniscus level in the ingot mold both during the application of said first periodic oscillating impulse and during the application of said second periodic oscillating impulse; c) comparing the oscillating frequency of the meniscus level in the ingot mold with the oscillating frequency of the first area of application during the application of said first periodic oscillating impulse, and comparing the oscillating frequency of the meniscus level in the ingot mold with the oscillating frequency of the second area of oscillation during the application of said second periodic oscillating impulse, wherein stage c) is carried out by comparing a frequency spectrum of a signal of the meniscus level in the ingot mold with frequency spectra of force or position of said first actuating cylinder and said second actuating cylinder, respectively; whereby if the compared spectra are superimposable, a liquid core is present in the cast product at the area where the periodic oscillating impulse is applied, otherwise the cast product is completely solidified, whereby if, by comparing the oscillating frequency of the meniscus level in the ingot mold with the oscillating frequency of the first area of application, the compared spectra are superimposable, and if, by comparing the oscillating frequency of the meniscus level in the ingot mold with the oscillating frequency of the second area of application, the compared spectra are not superimposable, a liquid core is present in the cast product at the first area while the cast product is completely solidified at the second area, the closing position of the liquid cone being thus included in said stretch of casting line. - an ingot mold containing the liquid metal and in which a meniscus is defined, - one or more soft reduction devices with rolls, - actuating cylinders for actuating said one or more soft reduction devices, - at least two areas of application of a periodic oscillating impulse along the casting line, said at least two areas defining end areas of said stretch of casting line, a) sequentially applying a first periodic oscillating impulse to a first area of application represented by a first actuating cylinder, thus causing a first oscillation on the cast product, and then a second periodic oscillating impulse to a second area of application represented by a second actuating cylinder, thus causing a second oscillation on the cast product; b) detecting the oscillating frequency of the meniscus level in the ingot mold both during the application of said first periodic oscillating impulse and during the application of said second periodic oscillating impulse; c) comparing the oscillating frequency of the meniscus level in the ingot mold with the oscillating frequency of the first area of application during the application of said first periodic oscillating impulse, and comparing the oscillating frequency of the meniscus level in the ingot mold with the oscillating frequency of the second area of oscillation during the application of said second periodic oscillating impulse,