The Blue Planet Aquarium is a marine and freshwater aquarium located by the Cheshire Oaks retail and leisure complex in Ellesmere Port, Cheshire, England. When opened by the Queen Elizabeth II in July 1998, it was the largest aquarium in the United Kingdom, and is still the largest in North West England. The £12 million building was designed by Manchester-based Buttress Fuller Alsop architects to resemble the shape of a crashing wave.