An aerofoil blade or vane for the turbine of a gas turbine engine is provided. The blade or vane includes an aerofoil portion which, in use, extends radially across a working gas annulus of the engine. A coolant inlet is formed at an end of the aerofoil portion for the entry of a cooling air flow into the portion. A corresponding coolant exhaust is formed at the trailing edge of the aerofoil portion for spent cooling air to flow from the portion. A passage within the aerofoil portion connects the inlet to the exhaust. A fence within the aerofoil portion extends radially and forwardly from a start position at the end of the aerofoil portion adjacent the trailing edge to an end position. The passage forms a loop which extends along one side of the fence, wraps around the end position, and extends along the other side of the fence.