Penders is a heritage-listed holiday retreat at Haighs Road (within Mimosa Rocks National Park), Tanja, Bega Valley Shire, New South Wales, Australia.

[3][1] When Grounds purchased the property in 1965, it had extraordinary scenic and natural qualities including a 1.6 kilometre frontage to the Pacific Ocean, and a northern boundary along the serene stretch of tidal estuary called Bithry Inlet.

Built structures include the minimalistic shelter, called the "Barn", the geodesic dome which framed a vegetable and herb garden, a wind generator tower, a covered orchard, the Myer house, a timber mill and various seats and benches around the bushland.

[1] Much of the Barn's character, its design influences and choice of materials and structure derives directly from Grounds's intent that Penders be a total escape from Melbourne and its professional ties.

It was to be a literal "bolt-hole", a place where Grounds could indulge in his own tinkering, entertain friends and family in peace, and be entirely removed from the pressures of the National Gallery of Victoria and the Victorian Arts Centre commission.

[3][1] The Penders property of 220 hectares was donated to the NSW Government to be incorporated as part of Mimosa National Park in 1976 by the owners, Sir Roy Grounds and Mr Kenneth Myer.

[11][1] Since this date, the area known as Penders has been managed by the National Parks and Wildlife Service (NPWS), part of the Office of Environment and Heritage (OEH) within the Department of Premier and Cabinet (DPC).

It became an object of influence in the immediate region due to the timber plantation and its mill and another Victorian architect Graeme Gunn completed the pole-framed Yencken House in 1969.

[12] However, the Barn post dates Ian McKay and Philip Cox's CB Alexander Presbyterian Agricultural College at Tocal (1963) which was also determinedly rural in its references to the simplicity of farm outbuildings and frank timber carpentry techniques.

A decorated student he was a one time junior architect at Blackett and Foster, a world traveler and a WWII veteran, Grounds was known for his experimental "Australian Style" (fusing living and dining areas) and became one of the leading exponents of modernism in house design.

In both private practice and as a lecturer at the University of Melbourne, Grounds grew up and contributed to a number of groundbreaking and often controversial mid 20th century architectural projects including distinctive house and flats (such as Moonbria); the Shine Dome at the Australian Academy of Science in Canberra; the National Gallery of Victoria and adjacent Arts Centre and the 18-storey tower at Hobart's Wrest Point Casino.

[1] Mimosa Rocks National Park covers some 5,804 hectares and extends northwards along the coast from the mouth of the Bega River for 20 kilometres to the southern shore of Bunga Lagoon.

Elsewhere, the park adjoins a mixture of forested and cleared freehold land that is primarily used for livestock grazing and a variety of residential and commercial developments on small rural allotments.

[1] Items on the Penders site include: As originally built, the "Barn" is a nine-sided structure with ten sloping poles forming the major framing elements, with no central support.

Complementing this space are two symmetrically placed fireplaces (that have been gas fired since installed), clerestorey lighting, and a massive dining table of three spotted gum slabs set permanently into the floor by six vertical Tanalith treated logs.

The entire arrangement was a tour-de-force of resourcefulness and making do - in absolute opposition to the hyper-technological solutions being developed overseas to waterproof, seal and connect the much larger geodesic domes designed by the form's inventor R Buckminster Fuller.

The second use was that the dome be a workshop for Roy Grounds, a place where he could tinker with experimental gadgets for Penders, work on maintenance jobs for the site, and also where he could indulge his interest in timber and rock sculptures.

[1] More recently, since the death of Kenneth Myer in 1992, the grounds have been managed by a reduced slashing schedule and the understorey of stands of marked trees has been allowed to regenerate and dams are showing signs of silting up under the pressure of extensive reed growth.

Most recently, Marr has expanded and improved the central fireplace with added wood storage and remounted the hot water service and installed an adjustable lamp and the hanging pantry and its pulley system of his own design.

The kitchen was located in the entry area, until Yasuko Myer organised to have it shifted to its current position around 1988, which was about the same time the Japanese bathroom was added (Joanna Baevski pers.

The structures collectively demonstrate an extreme in New South Wales in their level of experimentation with the return to rustic materials and finishes, the use of Tanalithic treatment process and log pole construction techniques.

The donation of the site to the state of NSW to expand the Mimosa Rocks National Park, is an expression of their philanthropy and their belief in public ownership of coastal lands across Australia.

The Pender's site has strong association with, and contains rare and key experimental works of Sir Roy Grounds (1905–81), one of Australia's most influential architects pioneering modernist design.

[1] The donation by Grounds and Myer of Penders to the State to expand the Mimosa Rocks National Park is a significant philanthropic contribution by enlightened individuals to the ongoing preservation of the natural environment.

The structures demonstrate an extreme in New South Wales in their level of experimentation at the time with the return to rustic materials, finishes, and the use of Tanalithic treatment process and log pole construction techniques.

[1] The "Barn", Sir Roy Grounds' iconic domestic masterpiece representing the latter phase (1960–81) of his career, is the most outstanding and creative work on site that features a permanent tent of deceptively simple design and overtly environmental aims.

The layered planning and the gradual transition in the character of the house from its modest unpretentious exteriors, to its surprising grand and finely detailed interiors add to its aesthetic quality.

[1] The special and unusual aesthetic qualities of the "Barn" and the Geodesic Dome have been recognised and highlighted in published papers by notable architectural historians Jennifer Taylor and Philip Goad.

[1] Penders also has contemporary social significance as a founding example of property purchased along the south coast or in the nearby bush where a series of like-minded intellectuals and artists from the major cities followed Grounds and Myer in building and occupying modest and environmentally sensitive structures as holiday retreats.

The "Barn" is an iconic representative example of the work of the fourth phase of Roy Ground's career, between 1960 and 1981, that was dominated by the commission for the National Gallery of Victoria and the Victorian Arts Centre.