Visit http://www.roofgardens.virgin.com/en/the_roof_gardens/the_gardens As of April 2009 the gardens have a brand new look .After a serious face-lift our rooftop gardens are once again open to the public on selected dates. As the gardens are hired for private events, please phone us on 0207 937 7994 a few days ahead to check availability.
There are three themed gardens sprawling over 1.5 acres including fully grown oaks and fruit trees, growing in just 1.5m of soil, and a flowing stream stocked with fish
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https://en.wikipedia.org/wiki/Kensington_Roof_Gardens