A turbine blade comprising: a blade portion, the blade portion comprising a tip outer wall and a tip trailing edge slot; an internal cooling circuit having a channel positioned radially inward from the tip outer wall and fluidly connected to the tip trailing edge slot for providing cooling air to the tip trailing edge slot, wherein the channel comprises a first portion and a second portion, the first portion being oriented generally parallel to the tip outer wall, the second portion being radially inclined with respect to the tip outer wall for guiding the cooling air flow in the radial direction; and the tip trailing edge slot being positioned adjacent to the tip outer wall and the trailing edge, the tip trailing edge slot being fluidly connected to the internal cooling circuit, wherein the tip outer wall is recessed at the tip trailing edge slot such that the tip outer wall is not provided over the trailing edge slot, thereby allowing cooling air to flow from the cooling circuit, into the trailing edge slot, and radially over the tip outer wall, the tip trailing edge slot comprising a radially lower wall, characterised in that the radially lower wall is radially declined with respect to the second portion and generally parallel to the first portion, the radially lower wall being configured to direct cooling air flow around the trailing edge, wherein the first portion and the second portion are fully bounded by outer and inner radial walls of the channel, wherein the second portion is provided between the radially declined radially lower wall and the first portion, such that the tip outer wall is not present over the radially lower wall, and wherein the inner radial wall of the first portion of the channel, the inner radial wall of the second portion of the channel, and the tip trailing edge radially lower wall form a contiguously- and continuously-connected channel radially lower surface. a blade portion, the blade portion comprising a tip outer wall and a tip trailing edge slot; an internal cooling circuit having a channel positioned radially inward from the tip outer wall and fluidly connected to the tip trailing edge slot for providing cooling air to the tip trailing edge slot, wherein the channel comprises a first portion and a second portion, the first portion being oriented generally parallel to the tip outer wall, the second portion being radially inclined with respect to the tip outer wall for guiding the cooling air flow in the radial direction; and the tip trailing edge slot being positioned adjacent to the tip outer wall and the trailing edge, the tip trailing edge slot being fluidly connected to the internal cooling circuit, wherein the tip outer wall is recessed at the tip trailing edge slot such that the tip outer wall is not provided over the trailing edge slot, thereby allowing cooling air to flow from the cooling circuit, into the trailing edge slot, and radially over the tip outer wall, the tip trailing edge slot comprising a radially lower wall, characterised in that the radially lower wall is radially declined with respect to the second portion and generally parallel to the first portion, the radially lower wall being configured to direct cooling air flow around the trailing edge, wherein the first portion and the second portion are fully bounded by outer and inner radial walls of the channel, wherein the second portion is provided between the radially declined radially lower wall and the first portion, such that the tip outer wall is not present over the radially lower wall, and wherein the inner radial wall of the first portion of the channel, the inner radial wall of the second portion of the channel, and the tip trailing edge radially lower wall form a contiguously- and continuously-connected channel radially lower surface.