Dinosaurs · Armoured dinosaur

Polacanthus

Say it pol-a-KAN-thus. The name means ‘many spines’.

Polacanthus beside a person 1.75 m tall. Ticks mark every metre.Body shape drawn for this site, showing the general build of armoured dinosaurs

Length: 5 m
Diet: Plant-eater
When: Early Cretaceousabout 125 million years ago
Fossils found in: England
Named by: Hulke (1881)
Family tree: Dinosauria › Ornithischia › Thyreophora › Ankylosauria

Where Polacanthus sits in the age of dinosaurs.Periods from the ICS chart; dinosaur dates from the Natural History Museum

Armoured dinosaurs. Plated and armoured plant-eaters, such as Stegosaurus and the ankylosaurs. See all 33

Found in Britain. Fossils of Polacanthus have been found in the United Kingdom. Read about how Britain moved across the globe in Britain's journey.

Lived at the same time

Baryonyx · same country
Eotyrannus · same country
Hypsilophodon · same country
Iguanodon · same country
Neovenator · same country
Pelorosaurus · same country
Valdosaurus · same country
Afrovenator

Other armoured dinosaurs

Gobisaurus Early Cretaceous
Minmi Early Cretaceous
Sauropelta Early Cretaceous
Shamosaurus Early Cretaceous
Silvisaurus Early Cretaceous
Nodosaurus Early Cretaceous
Cedarpelta Early Cretaceous
Gastonia Early Cretaceous

Source: Polacanthus in the Natural History Museum Dino Directory, read 12 November 2026. Sizes are the museum's estimates for a typical adult. "Lived at the same time" lists dinosaurs whose dates overlap, which does not always mean they met.