A prominent coastal landform, a steep and often vertical column of rock stands isolated in the sea near a coastline. These geological features are remnants of headlands eroded by wave action over extended periods. For instance, the Needles off the Isle of Wight in England exemplify this type of coastal structure.
Such formations provide important habitats for seabirds and other marine life, contributing to local biodiversity. They are also significant for understanding coastal erosion processes and geological history. Furthermore, these imposing structures can be iconic landmarks, attracting tourism and contributing to regional economies.