A muffler for an exhaust system of an internal-combustion engine, comprising: - a muffler housing with a peripheral wall, elongated in the direction of a longitudinal axis of the housing, and with a front wall (22, 24) on each axial end region (18, 20) of the peripheral wall, - a muffler insert, surrounded by the peripheral wall and supported on the peripheral wall, with at least one retaining wall extending substantially in the direction of the longitudinal axis of the housing, - at least one first exhaust-gas routing pipe, wherein said at least one first exhaust-gas routing pipe is an inlet pipe and is positioned with a first end region engaging in a peripheral-wall opening in the peripheral wall and is secured to the peripheral wall by welding and is secured by a second end region to the at least one retaining wall, wherein the at least one first exhaust-gas routing pipe is of multi-part design, wherein a first pipe part of the at least one first exhaust-gas routing pipe provides the first end region of the at least one first exhaust-gas routing pipe, positioned so as to engage in the peripheral-wall opening and secured to the peripheral wall by welding, and a second pipe part of the at least one first exhaust-gas routing pipe provides the second end region of the at least one first exhaust-gas routing pipe, secured to the at least one retaining wall, wherein the first pipe part and the second pipe part have been inserted into one another in their adjacent longitudinal regions and overlap one another in a longitudinal direction of the at least one first exhaust-gas routing pipe, characterized in that the second pipe part has been connected to the at least one retaining wall by material closure; and in that the first pipe part has been inserted into the second pipe part, and the first pipe part and the second pipe part have been connected to one another by radial widening of the at least the first pipe part at least in its longitudinal region overlapping with the second pipe part, or in that the second pipe part has been inserted into the first pipe part, and the first pipe part and the second pipe part have been connected to one another by radial widening of at least the second pipe part at least in its longitudinal region overlapping with the first pipe part. - a muffler housing with a peripheral wall, elongated in the direction of a longitudinal axis of the housing, and with a front wall (22, 24) on each axial end region (18, 20) of the peripheral wall, - a muffler insert, surrounded by the peripheral wall and supported on the peripheral wall, with at least one retaining wall extending substantially in the direction of the longitudinal axis of the housing, - at least one first exhaust-gas routing pipe, wherein said at least one first exhaust-gas routing pipe is an inlet pipe and is positioned with a first end region engaging in a peripheral-wall opening in the peripheral wall and is secured to the peripheral wall by welding and is secured by a second end region to the at least one retaining wall, wherein the at least one first exhaust-gas routing pipe is of multi-part design, wherein a first pipe part of the at least one first exhaust-gas routing pipe provides the first end region of the at least one first exhaust-gas routing pipe, positioned so as to engage in the peripheral-wall opening and secured to the peripheral wall by welding, and a second pipe part of the at least one first exhaust-gas routing pipe provides the second end region of the at least one first exhaust-gas routing pipe, secured to the at least one retaining wall, wherein the first pipe part and the second pipe part have been inserted into one another in their adjacent longitudinal regions and overlap one another in a longitudinal direction of the at least one first exhaust-gas routing pipe, characterized in that the second pipe part has been connected to the at least one retaining wall by material closure; and in that the first pipe part has been inserted into the second pipe part, and the first pipe part and the second pipe part have been connected to one another by radial widening of the at least the first pipe part at least in its longitudinal region overlapping with the second pipe part, or in that the second pipe part has been inserted into the first pipe part, and the first pipe part and the second pipe part have been connected to one another by radial widening of at least the second pipe part at least in its longitudinal region overlapping with the first pipe part.