Improvements in or relating to tiled roofs

An interlocking roofing tile 40 comprises a tile body 41 extending between an underlock 42a and an overlock 42b. The overlock has an inclined recess 54b for receiving a ridge 52a of an underlock 54a of an adjacent tile. The recess of the overlock is of decreasing depth when viewed in a direction towards the tile body, spacing the thinnest part of the overlock from the tile body. In the event that a force is applied to the overlock the spacing reduces the bending moment at the thinnest part, thereby increasing the strength of the interlock. A portion of the recess may be of constant depth. The ridge of the underlock may be tapered. The overlock recess may be provided with a locator configured to be received in a recess of the underlock of an adjacent tile.