Woolmer Forest is a 1,298.5-hectare (3,209-acre) biological Site of Special Scientific Interest south of Bordon in Hampshire and West Sussex.

It lies within the western Weald in the South Downs National Park, straddling the border between east Hampshire and West Sussex.

These moisture-retaining habitats grade into complex acidic boggy wetlands of hummocks and pools, locally called "mires".

Centuries of forest management have shaped the surrounding belts of woodland, composed notably of beech Fagus sylvatica and pedunculate oak Quercus robur.

The discontinuous canopy favours a diverse understory, dominated by holly Ilex aquifolium, whitebeam Sorbus aria and rowan S. aucuparia with birches.

Traces of Roman villas have been discovered at Blackmoor, Kingsley and Liss, though ordinary people continued to live in roundhouses.

[9] Following the Roman withdrawal and the collapse of Romano-British culture, the first mention of the present toponym, as Wulfamere, the "wolves' pool", is a token either of reforestation of the landscape or a translation of a previous pre-Roman name.

In addition, the SAC supports a significant presence of North Atlantic wet heaths with Erica Tetralix, and transition mires and quaking bogs.

In relation to its dry heaths, Woolmer Forest is the only site in Britain that supports all six native reptiles (including the sand lizard Lacerta agilis and smooth snake Coronella austriaca) and all six native amphibians (including the great crested newt Triturus cristatus).

It also supports an outstanding invertebrate fauna and bird assemblage, including European nightjar Caprimulgus europaeus, wood lark Lullula arborea, Dartford warbler Sylvia undata, Eurasian hobby Falco subbuteo, hen harrier Circus cyaneus and merlin Falco columbarius.