It's been four years in the making and not without hitch.

But yesterday came the iconic moment when Folkestone gained a new memorial that will mark the centenary of Britain's involvement in the First World War before commemorations with Prince Harry on August 4.

The town will be a focal point of the nation's commemorations that day with His Royal Highness officially unveiling the arch and the surrounding garden.

The new Arch on The Leas is a project by charity Step Short - which is also running several projects with schools in Shepway to educate children about the war and working in partnership to provide several exhibitions in Folkestone during the next four years.

Philip Gearing, of Hythe-based firm Foster Gearing, designed the arch. He said: "The idea that in 100 years time this will still be here but everything else may have changed. Maybe people will think what it was like going up and we're watching it being erected.

"I was asked to design an arch and chose this area because people could get to it. It's been on my computer for two years and it's kind of odd seeing it in 3D.

"We created an outdoor classroom, it's quite an interactive space. There's a compass which tells the story of the various countries that sent people through Folkestone.

"They can use it for geometry and maths, geography, history and storytelling.

"There's a big planter come bench opposite the seaside with an audio facility that will play recordings and stories about World War One, poetry and songs.

"In the very top there are 100 man made diamonds and their backlit. As you walk underneath them they will prism, twinkle and change colour. It's like 100 tiny stars.

"It's quite shiny. During the course of the day and the year the way it reflects light will change dramatically. So I'm interested to see people here with the cameras and mobile phones photographing it from different angles.

"In front it will be black or dark purple. Behind you it will be white orange, pink depending on the colours. I'm interested to see how this will become a subject for people to paint or photograph.

"What it's commemorating is sombre and awful but we've tried to use technology in a reverse way. It was hard to build and lots used in this interactive space.

"This is a symbol of something that was terrible but something ultimately that was pretty heroic for a lot of people."

Although not without its critics, Folkestone was a hugely significant town during the conflict.

Mr Gearing added: "This arch is a symbol about people who made a big sacrifice for the freedom for us to think what we want to think to criticise and complain. I don't agree but I support their right to."

Building the memorial will serve to mark the role Folkestone played and commemorate the thousands of lives lost and millions of men and nurses who left the harbour bound for the horrors of the battlefield.

It replaces an arch that stood at the top of the Road of Remembrance (which was renamed from The Slope Road after the war) during the 1920s and 1930s.

The Step Short project is sponsored by Kent County Council, Shepway District Council, the Roger De Haan Charitable Trust and several private donors as well as the Radnor Estate, the Don Hanson Charitable Foundation and EDF Energy.

The arch has cost £214,000 to build, with the work carried out by Lend Lease who offered their services for free.