Trafalgar Square in London has been covered in grass.
More than 2000 sq m of turf has been laid as part of a campaign called London Villages.
For two days, visitors to the square will be able to soak up the sunshine in deckchairs, enjoy a picnic, ortake part in a Tai Chi class.
It is the first time the Square has been turned into a garden.
The Visit London campaign aims to raise awareness of green spaces in the capital. Visit London chief executive James Bidwell said, "From the rural feel of areas like Bexley Village and Wimbledon, to urban villages like Marylebone and even Canary Wharf, the campaign will help everyone discover Village London."
After the event, the turf will be transferred to Bishops Park in Fulham, where it will be planted close to an avenue of plane trees.
The 40 tonnes of turf were laid in 1m-wide strips, 20m long, and watered. The turf came from Lindum in the Vale of York - an area that has a light, sandy soil. Growing a turf crop stabilises the soil by the tremendous root biomass built up.
Visit London's Ken Kelling said, "Hopefully people coming down specifically to see it and those who are just passing by will be able to enjoy it in the sunshine. Once they have enjoyed something unusual like this they could go on to explore other green areas across the capital."
A spokesman for Visit London said Global Cool, a celebrity-backed climate change campaign, would work with them to make the Trafalgar Square village green carbon neutral.
Global Cool would advise Visit London on how to reduce the event's carbon footprint before offsetting any remaining emissions.
