Carex riparia, the greater pond sedge, is a species of sedge found across Europe and Asia. It grows in a variety of wet habitats, and can be a dominant species in some swamps. It is Britain's largest Carex, growing up to 130 cm (4 ft 3 in) tall, with glaucous leaves up to 160 cm (5 ft 3 in) long. It hybridises with a number of other Carex species, including the closely related Carex acutiformis – the lesser pond sedge. A variegated cultivar is grown as an ornamental grass.