By Tom Geoghegan
BBC News Magazine
Plans for a £1m monument to the victims of the 7 July 2005 bombings have been posted online. But how are tragic events best marked by a modern memorial?
Erecting an appropriate monument to the dead is a delicate business.
Years after those personally touched by the loss of life have themselves passed away, how does it remain relevant?
A representative figure, an "unknown soldier", has historically been used for reflection and remembrance of victims of war.
But in recent years, monuments have become more abstract and artistic in conception, with sometimes controversial results, especially when trying to convey the horror of a terrorist attack or genocide.
On Wednesday, Westminster Council published on its website the planning application for a new £1m, 7 July memorial in London's Hyde Park.
What can be learnt from famous memorials elsewhere in the world?
The new memorial to be unveiled on 7 July next year will consist of 52 three-metre (10ft) tall, stainless steel pillars, grouped in four clusters, representing the four separate attacks of 2005.
Uneven ground disorientates in Berlin
A similar concept is used in Berlin's Holocaust Memorial, where visitors walk among 2,700 tilting, concrete slabs on uneven ground, designed by US architect Peter Eisenman.
"A graveyard memorial was something that you looked at but with the Berlin piece you're amongst it," says Jonathan Banks of Ixia, a national forum for public art.
"It's an attempt to convey a feeling of the horror that is being commemorated. You do feel cool and you do feel distant and you feel almost a weight above you. That's about trying to convey the experience - or some sense of the experience - of the event or some sort of sense of disorientation which is as physical as it is intelligent."
Also taking this theme, the New Zealand war memorial at Hyde Park Corner has 16 cross-shaped, vertical bronze standards which some say resemble warriors.
All Blacks at New Zealand's memorial
"Each stele [slab] has an individual marking reminiscent of New Zealand, which tells you about the flora, fauna and history," says Ian Leith, deputy chairman of the Public Monuments and Sculptures Association. "Therefore it's an extremely dense memorial and it's extremely exciting."
But he's less impressed with the location chosen for the 7 July memorial, because not enough people will see it, especially at a time when scores of London's public spaces for art could be under threat.
Flowing water is thought of as reflective and soothing, and reminiscent of time passing.
The aim was for children to play in the water - but it's been deemed too slippery
But the Diana, Princess of Wales Memorial Fountain, also in Hyde Park, opened to muted reaction - and safety problems - in 2004.
Richard Cork, an art critic who writes for the Times and the New Statesman, was on the panel that chose the design by Kathryn Gustafson. But it wasn't his choice and he's not a fan.
"I don't find it very special. It's quite ordinary. Some of us on the jury wanted Anish Kapoor who put forward a wonderful design, rising out of the Serpentine Lake, with seats either side like an amphitheatre so people could sit down and contemplate.
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"We had to think hard about what Diana was like and who she was and what she meant to people. In the end we thought Anish's proposal caught the spirit of Diana's character and that it would excite people. They would travel from all over to visit it."
But the panel was split, and those in favour of Kapoor's design were overruled.
The 9/11 memorial in New York will consist of two massive pools set within the footprints of the Twin Towers, with the country's largest manmade waterfalls cascading down their sides.
Washington DC's Vietnam Veterans' Memorial is one of the biggest visitor attractions in the United States, and other memorials since it opened in 1982 have followed its abstract principles.
Its two black granite walls, designed by Maya Ying Lin, bear the names of 58,256 people killed or missing.
DC's influential Vietnam War memorial
"You can't go through the main street of the capital of the most powerful country on Earth without seeing it," says Mr Leith.
"It's like a trench in the landscape and you can't help but realise the enormity of this trench and the wall of names and that's what has the effect. It's very effective because it's so simple."
There's always a danger artists can get too excited and too ostentatious, says Mr Cork. "I don't think showing off in a memorial is an appropriate thing to do at all and that's why the Vietnam one in Washington works so well. It's utterly minimal."
The Menin Gate Memorial in Ypres, Belgium, built in 1927, has 54,896 names of soldiers killed nearby in World War I, and every evening buglers visit to sound the Last Post.
In London's Whitehall there are good and bad examples, says Mr Cork.
Are massed pillars a modern take on the Cenotaph?
The Cenotaph, designed by Sir Edwin Lutyens and completed in 1920, generates enormous public feeling and its strength lies in its restraint and its nod to classicism.
"It's very moving because it's so simple and monumental and definitive. It's lodged itself in everyone's mind, unlike the more recent one to the women of World War II."
This 22ft-high bronze sculpture, unveiled three years ago, depicts the uniforms and working clothes worn by women of this era.
"I don't understand the significance of that," says Mr Cork. "I can't get why that was considered a good way to memorialise the women of WWII, to have empty coats.
"It doesn't say anything about their contribution and it rather underplays their role. It's very puzzling and quite annoying."
Mr Cork says the best memorial he has seen is by Constantin Brancusi and can be found in the Romanian city of Tirgu Jiu. It honours the WWI dead and comes in three parts.
Brancusi's Tirgu Jiu memorial (photos by Jackie Kirkham on Flickr)
"It's quite staggering and moving. It starts off with a series of empty chairs around an empty round table and then you walk in a line through a park towards a kind of gate.
"It's got embracing figures curved into the stone and then you walk quite a way right through the town in a straight line and gradually you come to this thing up ahead of you which is this incredible column climbing into the sky.
"It's very isolated so in that respect it's very alone but the fact it's shooting upwards, it's not too melancholy. There's some sort of hope there, especially for people who are religious."
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