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Singapore -

Labeled as a hotel-in-a-garden, Parkroyal Collection Pickering, Singapore features a series of sky gardens designed to be self-sustaining and consume minimal energy through the use of solar cells, motion sensors, rainwater harvesting, and reclaimed water.

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Scotland -

An architect-designed modern building with a garden roof located just off Princes Street in Edinburgh. Incorporating a green roof on buildings can help cut energy costs by keeping the building warmer in winter and cooler in summer.

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England -

Urban beekeeping has boomed in popularity over the past decade as green rooftops have evolved. Pictured is a beekeeper at work on a residential property in Islington, London.

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China -

A dizzying aerial view of a rooftop garden on a fifth floor parking lot in Chengdu. In recent years, many buildings in the country's biggest cities have established rooftop farms.

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Iceland -

The most basic of green roofs are those found on traditional Arctic and Scandinavian dwellings that are covered with sod placed on top of several layers of birch bark.

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USA -

Chicago City Hall's rooftop garden consists of 20,000 plants of more than 150 species, including shrubs, vines, and two trees.

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Japan -

The Acros Fukuoka building in Fukuoka comprises a huge terrace roof that contains some 35,000 plants representing 76 species. As such, the property appears to merge with the park.

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England -

London's attractive Cannon Street Station and Cannon Bridge Roof Garden.

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France -

Rather than a roof garden, the Musée du quai Branly–Jacques Chirac in Paris features a green wall that includes 15,000 plants of 150 different varieties originating from Japan, China, the Americas, and Central Europe

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Germany -

This is the Waldspirale, a residential building complex in Darmstadt. The name translates into English as forest spiral, reflecting both the general plan of the building and the fact that it has a green roof.

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USA -

The five roof gardens carpeting the seventh floor of the Rockefeller Center in New York City have been in existence since the mid 1930s. Three of the gardens can be viewed from the Top of the Rock observation decks.

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Italy -

The quirky Torre Guinigi in Lucca, Tuscany is known for the holm oaks growing on top of the tower.

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Australia -

The Council House 2 administration building in Melbourne has a substantial rooftop garden area. The high-rise horticultural attraction helps cool urban heat islands—a metropolitan area that is significantly warmer than its surrounding rural areas due to human activities.

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Netherlands -

Architecture and Nature exist as one at the Biesbosch Museum at Werkendam. The facility is set on a man-made island.

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England -

City workers enjoy lunchtime high above London on the rooftop garden at Fen Court, located in the capital's financial district known as the Square Mile.

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USA -

Visitors to Lurie Garden in Chicago can join a guided walk to learn more about the flora that endow the world's largest green roof.

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Germany -

What appears to be a ground-level garden at Frankfurt's Städel Museum is, in fact, the green roof covering a subterranean extension of the museum's exhibition hall.

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England -

Crossrail Place Roof Garden at London's Canary Wharf is a tropical oasis hidden beneath a distinctive, timber latticed roof.

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USA -

The High Line is an elevated linear park in New York City. A novel tourist attraction, the greenway encapsulates landscape architecture, urban design, and ecology.

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Singapore -

The top of the incredible Cloud Forest at the Gardens by the Bay is accessed by elevator, after which you descend via a spiral walkway passing flowers and tropical vegetation and a 35m (115ft) waterfall.

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England -

London's second-largest conservatory is located at the Barbican Centre. Home to exotic fish and over 1,500 species of tropical plants and trees, the green space is designed as part of a roof structure and also features a restaurant.

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USA -

Located in San Francisco's Golden Gate Park, the California Academy of Science—the oldest museum in the state—supports a green roof planted with 1.7 million California native plants.

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England -

London's National Theatre terrace and upper deck garden café.

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Japan -

The Namba Parks office and shopping complex in Osaka features a rooftop park of trees, clusters of rocks, cliffs, lawn, streams, waterfalls, ponds, and outdoor terraces.

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England -

The upscale Coq d'Argent French restaurant in central London offers diners a rooftop terrace and garden dining option.

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USA -

Two gardeners working at the Brooklyn Grange, a rooftop commercial garden located in Queens, New York City.

See also: Simple lifestyle changes that help the environment

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