Large, ancient marine reptiles belonging to the superfamily Chelonioidea, distinguished by their streamlined bodies, flipper-like limbs for swimming, and a diet primarily of jellyfish, seagrass, or crustaceans depending on the species.

Seven extant species (six hard-shelled in Cheloniidae and one leatherback in Dermochelyidae), many of which are endangered due to threats like habitat loss, poaching, and plastic pollution; they undertake epic migrations to nest on beaches worldwide.

Iconic ocean dwellers known for laying eggs in sandy nests, with hatchlings making a perilous dash to the sea, often depicted as wise wanderers in marine folklore.