Donnelly Flat is a natural grassy clearing of a few acres set along the Atiwhakatu Stream in the Holdsworth area of Tararua Forest Park, Wairarapa.

Its sheltered position in the valley and easy stream access have long made it a favourite spot for picnickers and campers. The flat is reached via a 2.

5 km loop walk from the Holdsworth car park, crossing the Atiwhakatu footbridge and following a relatively level track through some of the finest mixed podocarp-broadleaf bush in the region.

The site takes its name from Thomas Donnelly, a Masterton prospector who established a camp here in the early 1900s. He disappeared in April 1910 and his remains were found a year later, with evidence suggesting he had fallen and died of exposure.

Donnelly Flat sits roughly 20 minutes from Holdsworth Lodge and also serves as a waypoint on longer routes into the Tararua Range, including the popular Jumbo Circuit.