A wave-cut platform is a narrow, flat area formed at the base of sea cliffs due to erosion from destructive waves during storms. Destructive waves undermine the cliff face through hydraulic action and corrasion, creating a wave-cut notch. Continued erosion enlarges the notch until the cliff above collapses, exposing a flat terrace known as a wave-cut platform. As the cliff continues retreating inland, the platform grows wider.