As with any other vegetable farm, the Brooklyn Grange farm in New York is a large plot filled with neat rows of leafy greens like kale, arugula and lettuce.
But what is different about this half-hectare farm is that it is 11 storeys off the ground and has a view of the Manhattan skyline.
Started by 34-year-old Ben Flanner, the farm is one of the success stories in New York City's drive for green spaces.
"We have 12 million people in the city and a lot of them don't have the means to see how food is grown," said Mr Flanner. The farm is open to visiting school groups and rents out some spaces for public events.
"We are proud of having created a green space and it makes the city more liveable as it gets denser and denser," Mr Flanner said.
Brooklyn Grange was among the sites visited by a Singapore team on Monday ahead of the World Cities Summit Mayors Forum which wraps up tomorrow.
While Singapore has not fully embraced the idea of rooftop farms, the Government has been increasingly encouraging the use of rooftops as green spaces.
As of last July, there were about 28ha of greenery spread over 160 roofs of HDB blocks and carparks. During the next few years, that number is expected to more than double.
The Singapore delegation to the summit is led by Minister of State for National Development Desmond Lee. Others in the delegation include Second Permanent Secretary for National Development Chew Hock Yong, Mr Khoo Teng Chye, executive director of the Centre for Liveable Cities, Mr Ng Lang, CEO of the Urban Redevelopment Authority (URA), and Holland-Bukit Timah GRC MP Liang Eng Hwa, who is also a URA board member.
The World Cities Summit, now in its sixth year, brings together mayors and city leaders to exchange ideas on developing sustainable cities. Leaders from some 70 countries are due to attend the meeting, which is jointly organised by the Centre for Liveable Cities and the URA.
Mr Khoo told the media that the summit has been a useful platform for mayors, the private sector and global organisations.
"... there is a lot that we can find in common between big, successful cities like New York and smaller cities," he said.
This year marks only the second time the summit is being held outside of Singapore. New York was chosen as host because it won the 2012 Lee Kuan Yew World City Prize in recognition of the way it had bounced back and rejuvenated itself after the Sept 11 terrorist attacks.
The Mayors Forum will feature speeches from Mr Lee, New York Mayor Bill de Blasio and UN Deputy Secretary-General Jan Eliasson.
The two-day forum will also include some 30 presentations from city leaders on topics such as housing, transportation, sustainability and education.
At the end, mayors and city leaders are due to sign a joint declaration pledging commitment to sustainable development.
This article was first published on June 10, 2015.
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