An ''eccentric'' Russell lodge owned by an colourful Italian winemaker has been named the world's best eco-friendly hotel.
Donkey Bay Inn, which is built into a hillside near Long Beach, was also named Australasia's most inspired design hotel at the World Boutique Hotel Awards held in London.
Owner Antonio Pasquale said 300 nominees from 80 countries contested the awards and expert judges personally visited every finalist.
That gave the awards ''a rare and robust credibility'', he said.
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The inn opened in late 2017 but was originally designed as a private home 15 years ago by architect Gary Underwood, who described it as a ''designer's dream''.
''Architecture can only be as good as the client lets it. Builder Howard Harnett, Antonio Pasquale and I all talked the same language. The curved, soaring structure was not designed to a price,'' he said.
Underwood said he had been inspired by the ''hearty design'' of the 400-year-old Pasquale family home in Italy.
The huge hardwood beams that radiate across the building and give it much of its character were salvaged by Pasquale when they were ordered, but not required, for the America's Cup races in Auckland.
Interior designer Patrick Crawshaw turned what had been a home into a unique eco-hotel, creating a style he described as ''Alice in Wonderland meets Salvador Dali''.
''I wanted guests to feel as though they were entering another world. My aim was to turn everything one expects from a hotel on its head.''
The inn has just four rooms overlooking the Bay of Islands, a walled courtyard, outdoor baths, large decks and butler service.
It has large double-glazed curved windows, solar underfloor heating and is entirely off-grid. The largest living roof in the Southern Hemisphere makes it almost invisible from the air.
The property also has a vineyard, an olive grove, beehives, chickens and organic vegetable gardens.
The awards were announced last month and accepted by inn manager Amelia Styles.
The judges summed Donkey Bay Inn up as ''soulful, eccentric, vibrant and deeply inspiring'' and ''an eclectic masterpiece overlooking one of the world's finest coastlines''.
The other finalists included a lakeside lodge in a 64,000ha African game reserve, a Caribbean resort, a Borneo rainforest lodge, and a castle in the Scottish Highlands.
It was the first time Donkey Bay had entered the awards.
Room rates range from $770 to $1270 a night. Breakfast is included, as is a welcoming drink from Pasquale's own vineyard.
Other meals are not provided but staff can take guests to Russell restaurants in one of the hotel's Daimlers.