A continuous casting and rolling plant for the continuous production of steel bars or profiles, the plant comprising in sequence, along a processing line, a continuous casting machine adapted to cast a billet; a first cutting device; a second cutting device; a rolling train adapted to roll the billet; wherein the continuous casting machine comprises a crystallizer, and is adapted to cast the billet at least at a first casting speed v1 and at a second casting speed v2 greater than the first casting speed v1; wherein the first cutting device is arranged at a first distance from the crystallizer expressed in meters, along the processing line, calculated according to a specific mathematical relation.