Portishead Dock was built in the 19th century at the point where the river Avon runs into the Bristol Channel, and served shipping from around the world. In 1929 a coal-fired power station was built at the dockside, providing electricity for nearby Bristol, and a second station which used both coal and oil was added in the 1950s. The chimneys for these power stations were a well-known local landmark, but the power stations were closed in the 1980s and the chimneys were later demolished.

Today Portishead Dock is a busy marina for everything from dinghies to multi-million pound yachts, and housing, shops and restaurants have been built around the edge.