With space ever at a premium in the world's rapidly expanding cities, could the secret of adding green spaces be to build them vertically? That's what the planners behind these concepts and existing vertical forests are banking on.
But it is not just to make cities more bearable to look at. By adding vegetation to the building's exterior, air quality in the city, and energy efficiency within the buildings can greatly benefit.
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What are some examples of vertical forests from around the world?
So, without further ado, here are some amazing examples of vertical forests from around the world. This list is far from exhaustive and is in no particular order.
1. Nanjing in China has some interesting vertical forests

The city of Nanjing in China has been making a push to "greenify" some of its tower blocks. Called "Living Towers," these multistorey buildings, once built, will be covered with thousands of living, breathing (well photosynthesizing) trees.
Such initiatives might just be the future of many tall buildings around China and the world.
2. This "Smart Forest City" concept for Cancun is awesome

Stefano Boeri Architetti has an interesting vision for future development in Cancun, Mexico. Covering around 557 hectares, their concept for a "Smart Forest City" could house around 130,000 people.
Almost everywhere conceivable within the development would have planted surfaces, including upwards on building facades and roofs. With so much vegetation, it would be difficult to remember that you are actually living in a city.
3. Egypt may soon be home to Africa's very first vertical forest

In collaboration with the Egyptian designer Shimaa Shalash and Italian landscape architect Laura Gatti, Stefano Boeri Architetti are also making plans for Egypt's very own first-of-a-kind vertical forest.
Designs for a trio of living buildings were released last year for Egypt's planned New Administrative Capital just east of Cairo.
"The buildings will have planted terraces containing 350 trees and 14,000 shrubs of more than 100 different species. One of the three buildings will be a hotel, while the other two will house apartment units." - World Economic Forum.
4. Milan, Italy has its own pair of vertical forests already

The city of Milan in Italy is yet another city that has been gifted with its own vertical forests. Called the "Bosco Verticale" (vertical forest in Italian), the twin living towers are home to over 20,000 plants and were completed in 2014.
These plants not only produce oxygen and consume carbon dioxide, but they help to attenuate noise and act as passive temperature regulators for the building.
5. Utrecht in the Netherlands is planning to build their own vertical forests as well

The city of Utrecht in the Netherlands is also planning to build their own vertical towers sometime in the future. Planners are keen to reinvigorate biodiversity in the local area by planting over 10,000 plants on a tower's facade.
6. This vertical forest in Milan, Spain is quite stunning

The exterior of the Caixa Forum Museum in Madrid is another amazing example of a vertical forest. Reaching for up to 4 stories high, this vertical green space consists of around 15,000 different plants from more than 250 species.
It also looks pretty cool too.
7. This vertical forest in Singapore is quite beautiful too

The outside of The Oasia Downtown Hotel is another amazing example of a vertical forest from around the world. Located in the heart of the city's business district, this building really does stand out.
8. These vertical forests in Kaula Lumpur City are also impressive

In the heart of Kuala Lumpur City in Malaysia, several amazing vertical forests can also be found. Designed by architect Jean Nouvel, these amazing buildings were built in 2016.
Called "Le Nouvel Towers" these vertical towers certainly add some much-needed nature to the center of this modern city.
9. The city of Cebu in the Philippines is hoping to get its own vertical forest too

And finally, the Filipino city of Cebu is also set to get its very own vertical forest too. Much like other buildings on the list, the addition of vegetation to the building's exterior will provide a great passive way to fight pollution and reduce heating and cooling costs throughout the year.
Called "The Rainbow Tree," this amazing vertical forest concept building has been designed to combine functionality and elegance using natural, simple, and traditional materials.