Woodwalton Marsh is a 0.8-hectare (2.0-acre) biological Site of Special Scientific Interest north-east of Woodwalton in Cambridgeshire.

[1][2] It is managed by the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire.

[3] This grassland on calcareous clay has diverse flora, including red fescue, quaking grass, knapweed, cowslip, pepper saxifrage, green-winged orchid and the rare sulphur clover.

[4] There is also a wide variety of butterflies.

[3] There is access from New Road.