The Hollywood sign above Los Angeles was unveiled in 1923
A nature conservation group is to cover up the iconic Hollywood sign in a campaign to stop luxury houses being built on the hill around it.
The Trust for Public Land has obtained permission to cover the sign with the words "Save The Peak".
It is racing to raise some $5.2m (£3.3m) needed to buy the land under a special deal that expires in April.
The land belongs to a property developer and its value has dropped sharply during the economic crisis.
The Trust for Public Land has already raised about $7m (£4.5m) towards the cost of the parcel of land known as Cahuenga Peak.
The owner, Fox River Financial Resources, put it on the market two years ago at $22m (£14m), but the price has fallen to $12m (£7.6m).
Page Rausser, of the Trust for Public Land, told the BBC that the group had obtained permission to cover the sign for up to five days.
She said the group had decided on the move to remind people "that the backdrop is part of the iconic nature of the sign".
"We are worried about mega-mansions being built up on the ridge line right behind the Hollywood sign," she said.
She added: "I think we all feel confident that we're going to raise the money we need because this is such an important property to Los Angeles."
The sign in the Hollywood hills was unveiled in 1923 and quickly became a tourist attraction.
It cost $21,000 (£13,500) to erect and originally spelt out "Hollywoodland", an advertisement for a housing development.
Fox River, a Chicago-based developer, bought the site near the sign in 2002 from the estate of movie mogul Howard Hughes.