A tire comprising: a tread; a pair of sidewalls disposed inwardly of the tread in a radial direction so as to be continuous with ends of the tread; a pair of beads disposed inwardly of the sidewalls in the radial direction; a carcass disposed inwardly of the tread and the pair of sidewalls so as to extend on and between one of the beads and another of the beads; a belt disposed between the tread and the carcass in the radial direction, the belt including multiple belt cords aligned with each other; an inner liner disposed inwardly of the carcass; and a pair of fixing layers spaced from each other in an axial direction, wherein the tread has a circumferential groove formed therein, and a groove depth of the circumferential groove is not greater than 7.0 mm, wherein the tread comprises a cap layer and a base layer covered by the cap layer, wherein a loss tangent of the cap layer at 30°C is not greater than 0.30, and wherein each fixing layer is disposed between the cap layer and the carcass in the radial direction, characterized in that a loss tangent of the base layer at 30°C is less than the loss tangent of the cap layer at 30°C, a first end of the fixing layer is disposed outwardly of an end of the base layer in the axial direction, or a position of the first end of the fixing layer coincides with a position of the end of the base layer in the axial direction, adhesiveness of each fixing layer is higher than adhesiveness of the cap layer, and the base layer is disposed inwardly of a reference end of the tread in the axial direction, wherein, on the meridian cross-section, the contour of a tire outer surface includes, on each end portion of a tread surface, a curved line portion that is a curved contour line connected to a tire side surface and formed as an arc having the smallest radius among the plurality of curved contour lines included in the contour of the tread surface, wherein the reference end of the tread is a position, on the tread surface, corresponding to an intersection point of the tangent line LT and the tangent line LS, wherein the tangent LT is a line tangent to the curved line portion at a contact point, where, on the contour of the tire outer surface, the curved line portion is in contact with a contour line adjacent to the curve line portion on the inner side in the axial direction, and wherein the tangent LS is a line tangent to the curved line portion at a contact point, where, on the contour of the tire outer surface, the curved line portion is in contact with a contour line adjacent to the curve line portion on the outer side in the axial direction, with the loss tangent determined on a test piece sampled from the tire in accordance with the standard of JIS K6394 at a temperature of 30°C, an initial strain of 10%, a dynamic strain of 2%, a frequency of 10 Hz, in tensile deformation. a tread; a pair of sidewalls disposed inwardly of the tread in a radial direction so as to be continuous with ends of the tread; a pair of beads disposed inwardly of the sidewalls in the radial direction; a carcass disposed inwardly of the tread and the pair of sidewalls so as to extend on and between one of the beads and another of the beads; a belt disposed between the tread and the carcass in the radial direction, the belt including multiple belt cords aligned with each other; an inner liner disposed inwardly of the carcass; and a pair of fixing layers spaced from each other in an axial direction, wherein the tread has a circumferential groove formed therein, and a groove depth of the circumferential groove is not greater than 7.0 mm, wherein the tread comprises a cap layer and a base layer covered by the cap layer, wherein a loss tangent of the cap layer at 30°C is not greater than 0.30, and wherein each fixing layer is disposed between the cap layer and the carcass in the radial direction, characterized in that a loss tangent of the base layer at 30°C is less than the loss tangent of the cap layer at 30°C, a first end of the fixing layer is disposed outwardly of an end of the base layer in the axial direction, or a position of the first end of the fixing layer coincides with a position of the end of the base layer in the axial direction, adhesiveness of each fixing layer is higher than adhesiveness of the cap layer, and the base layer is disposed inwardly of a reference end of the tread in the axial direction, wherein, on the meridian cross-section, the contour of a tire outer surface includes, on each end portion of a tread surface, a curved line portion that is a curved contour line connected to a tire side surface and formed as an arc having the smallest radius among the plurality of curved contour lines included in the contour of the tread surface, wherein the reference end of the tread is a position, on the tread surface, corresponding to an intersection point of the tangent line LT and the tangent line LS, wherein the tangent LT is a line tangent to the curved line portion at a contact point, where, on the contour of the tire outer surface, the curved line portion is in contact with a contour line adjacent to the curve line portion on the inner side in the axial direction, and wherein the tangent LS is a line tangent to the curved line portion at a contact point, where, on the contour of the tire outer surface, the curved line portion is in contact with a contour line adjacent to the curve line portion on the outer side in the axial direction, with the loss tangent determined on a test piece sampled from the tire in accordance with the standard of JIS K6394 at a temperature of 30°C, an initial strain of 10%, a dynamic strain of 2%, a frequency of 10 Hz, in tensile deformation.