The smaller of the two towers, at 355ft high, will feature a Hyatt hotel, complete with rooftop swimming pool, while the taller tower will host offices, a museum, a green architecure school and a private rooftop club.

The towers, designed by Italian architect Stefano Boeri, are due to be finished by 2018. Boeri completed his first vertical forest project in Milan in 2014. The Milan towers have created a vertical environment which can also be utilised by both birds and insects and it's hoped that the Nanjing buildings will do the same.

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Although the Nanjing towers will be the first 'vertical forests' in Asia, other hotels have attempted similar concepts: PARKROYAL on Pickering in Singapore features more than 15,000 square-metres of gardens, waterfalls and planter terraces on its exterior. Our reviewer Helen Coffey says: "it's a hotel-in-a-garden, with four floors boasting balconies covered in lush greenery."