The Mayor, Landscape Institute and the Garden Museum recently ran a competition to find fresh ideas for new green spaces and places in London.
The competition attracted 170 entries from across the world including China, India and Brazil, and you can see the 20 shortlisted entries in this new exhibition at City Hall.
The competition was inspired by the success of New York's High Line, an urban park created from a disused railway line in Manhattan.
The shortlisted designs range from huge city-wide ideas, such as using the empty space on top of buses, trams and trains for mobile gardens, to small-scale local projects, like miniature urban woodlands in London's forgotten spaces.
'Pop Down' the winning entry by Fletcher Priest Architects creates an urban mushroom garden lit by sculpted glass-fibre mushrooms at street level inside the 'Mail Rail' tunnels beneath Oxford Street.
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