Paganoni Swamp in Karnup is bounded by Paganoni Road to the north, Kwinana Freeway to the east, Southern Metro Rail to the west and the city boundaries of Rockingham and Mandurah to the south.
It is the southernmost reserve of Rockingham Lakes Regional Park. This Conservation Category Wetland is the largest in the Stake Hill Wetlands chain. The central wetland is surrounded by tuart and mixed woodlands of banksia and sheoak. To the east tuarts give way to jarrah and banksia woodlands, with heathlands on limestone ridges in the western part of the reserve.
Visitors can traverse the informal walktrails and firebreaks around the swamp, while the local Friends group sometimes holds fungi forays and bird walks.
Brushtail possums, quenda, brush-tailed phascogales, bobtails, western blue tongues, dugites, heath monitors and black headed monitors are among the attractive and abundant mammals found at Paganoni Swamp.