A tire comprising: a tread portion being provided with a plurality of circumferential grooves continuously extending in a tire circumferential direction, a plurality of lateral grooves extending in a tire axial direction, and a plurality of first blocks, wherein each of the plurality of first blocks is provided with at least one first sipe, the at least one first sipe extends in a zigzag shape in both of a cross-section perpendicular to a sipe length direction and a cross-section parallel to a ground contact surface of the respective first block, the at least one first sipe comprises a sipe bottom, and a tie-bar locally raising outwardly in a tire radial direction from the sipe bottom and terminating without reaching the ground contact surface of the respective first block to divide the at least one first sipe into a first portion and a second portion in the sipe length direction, the sipe bottom of the first portion communicates with a first widening portion having a circular shape in a cross-section perpendicular to the sipe length direction, the first widening portion has a groove width greater than a width of the first portion, the first widening portion extends linearly over an entire length thereof along the sipe length direction of the first portion, the sipe bottom of the second portion communicates with a second widening portion having a circular shape in a cross-section perpendicular to the sipe length direction, the second widening portion has a groove width greater than a width of the second portion, the second widening portion extends linearly over its entire length along the sipe length direction of the second portion, and the first widening portion does not communicate with the second widening portion, characterised in that the tread portion comprises a cap rubber layer forming the ground contact surface, and a base rubber layer disposed inwardly in the tire radial direction of the cap rubber layer and having a hardness greater than that of the cap rubber layer, wherein the hardness is measured by durometer type A in an environment of 23 degrees C in accordance with JIS-K6253, and at least a part of the first widening portion and the second widening portion is located in the base rubber layer. a tread portion being provided with a plurality of circumferential grooves continuously extending in a tire circumferential direction, a plurality of lateral grooves extending in a tire axial direction, and a plurality of first blocks, wherein each of the plurality of first blocks is provided with at least one first sipe, the at least one first sipe extends in a zigzag shape in both of a cross-section perpendicular to a sipe length direction and a cross-section parallel to a ground contact surface of the respective first block, the at least one first sipe comprises a sipe bottom, and a tie-bar locally raising outwardly in a tire radial direction from the sipe bottom and terminating without reaching the ground contact surface of the respective first block to divide the at least one first sipe into a first portion and a second portion in the sipe length direction, the sipe bottom of the first portion communicates with a first widening portion having a circular shape in a cross-section perpendicular to the sipe length direction, the first widening portion has a groove width greater than a width of the first portion, the first widening portion extends linearly over an entire length thereof along the sipe length direction of the first portion, the sipe bottom of the second portion communicates with a second widening portion having a circular shape in a cross-section perpendicular to the sipe length direction, the second widening portion has a groove width greater than a width of the second portion, the second widening portion extends linearly over its entire length along the sipe length direction of the second portion, and the first widening portion does not communicate with the second widening portion, characterised in that the tread portion comprises a cap rubber layer forming the ground contact surface, and a base rubber layer disposed inwardly in the tire radial direction of the cap rubber layer and having a hardness greater than that of the cap rubber layer, wherein the hardness is measured by durometer type A in an environment of 23 degrees C in accordance with JIS-K6253, and at least a part of the first widening portion and the second widening portion is located in the base rubber layer.