A turbine flowpath component for a gas turbine engine comprising: a platform defining at least one cooling cavity; a turbine flowpath component cover disposed radially outward of said platform, wherein the turbine flowpath component cover defines a radially outward edge of said at least one cooling cavity, wherein the turbine flowpath component cover further defines a transition region in which a radial depth of the at least one cooling cavity varies from a first depth to a second depth, characterised in that: the turbine flowpath component cover further defines a first region having a first radial depth on a first side of the transition region, wherein the first depth is a radial distance between the platform and the turbine flowpath component cover, and a second region having a second radial depth on a second side of the transition region, wherein the second depth is a radial distance between the platform and the turbine flowpath component cover and the transition region transitions from the first radial depth to the second radial depth; said first region is an upstream edge of said platform relative to fluid flow through a gas turbine engine, and said second region is a downstream edge of said platform relative to fluid flow through the gas turbine engine; and the second radial depth is less than the first radial depth. a platform defining at least one cooling cavity; a turbine flowpath component cover disposed radially outward of said platform, wherein the turbine flowpath component cover defines a radially outward edge of said at least one cooling cavity, wherein the turbine flowpath component cover further defines a transition region in which a radial depth of the at least one cooling cavity varies from a first depth to a second depth, characterised in that: the turbine flowpath component cover further defines a first region having a first radial depth on a first side of the transition region, wherein the first depth is a radial distance between the platform and the turbine flowpath component cover, and a second region having a second radial depth on a second side of the transition region, wherein the second depth is a radial distance between the platform and the turbine flowpath component cover and the transition region transitions from the first radial depth to the second radial depth; said first region is an upstream edge of said platform relative to fluid flow through a gas turbine engine, and said second region is a downstream edge of said platform relative to fluid flow through the gas turbine engine; and the second radial depth is less than the first radial depth. the turbine flowpath component cover further defines a first region having a first radial depth on a first side of the transition region, wherein the first depth is a radial distance between the platform and the turbine flowpath component cover, and a second region having a second radial depth on a second side of the transition region, wherein the second depth is a radial distance between the platform and the turbine flowpath component cover and the transition region transitions from the first radial depth to the second radial depth; said first region is an upstream edge of said platform relative to fluid flow through a gas turbine engine, and said second region is a downstream edge of said platform relative to fluid flow through the gas turbine engine; and the second radial depth is less than the first radial depth.