The oldest RSPB reserve in Wales and the only northern gannet colony in Wales.  With 36,000 pairs of breeding gannets it is the 3rd largest in the world behind Bass Rock and St Kilda.

The uninhabited rocky island of Grassholm lies 15 kilometres off the Southern Pembrokeshire Coast.  The island is remote and exposed and surrounded by difficult and turbulent seas.  This is an excellent area for feeding Porpoise, Common Dolphins and Rissos Dolphins.

Grassholm Island was the first RSPB island established in Wales in 1948 and no public landing is permitted.

The highest elevation is 42 metres.

The island comes alive in early spring, with gannets returning to the island from late February onwards.  The air is filled with males returning with nesting materials keen to establish territory ready to attract a female.

A single egg is laid in April and chicks begin to hatch in early June.  The chicks are then fed by both parents for 90 days until they are fully grown and ready to leave the island in late August and throughout September.

Lat/Lng: 51.731287, -5.479151          Grid Ref: SM598093