This marker on the Cambridge Butterfly Trail is at Logan’s Meadow local nature reserve – see the map above.

The British race of the Swallowtail is a unique UK subspecies, strictly tied to the fenland of the Norfolk Broads.

Its caterpillars depend solely on milk‑parsley for food. Once found in Cambridgeshire until the mid‑1950s, past reintroduction efforts failed due to inadequate food plant availability, although the Great Fen project are expanding suitable habitat across East Anglia.

It is the UK’s largest butterfly with a wingspan of 7.6 to 9.3cm, distinctive cream and black‑veined wings adorned with blue margins, red spots, and elongated ‘tails’ on the hindwings. This butterfly’s tail-like extensions resemble antennae, and along with its red and blue ‘false eyes’, they trick predators into mistaking the back of the butterfly for its head!

For more information, please visit Butterfly Conservation’s page on this species – Swallowtail.